experiments for gravity

Top 10 Gravity Experiments: Fun & Easy

Blow your mind with these easy and amazing gravity experiments!

Do you need a creative and engaging way to introduce students to the idea of gravity? Look not more than this collection of gravity experiments that students and teachers can perform in the classroom.

We’ve assembled a variety of experiments suitable for different age groups, covering concepts such as gravitational force, mass, weight, and free-fall motion. These hands-on, enlightening activities will not only help you grasp the fundamental principles of gravity but also ignite a lifelong fascination with physics.

1. Gravity-Defying Water Experiment

Students can learn more about the concepts of surface tension and the effects of gravity on liquids while having fun and being creative by trying out the gravity-defying water experiment.

2. Finding the Center of Gravity

The finding of the center of gravity experiment is an excellent way to introduce kids to the concept of balance and gravitational laws. These experiments also provide students with practical experience in learning the significance of the center of gravity in determining an object’s stability.

3. Anti-Gravity Galaxy in a Bottle

The anti-gravity galaxy in a bottle experiment is an engaging and innovative way to introduce children to the concepts of density and liquid characteristics.

Students can create a container that appears to defy gravity and gives the appearance of a galaxy by filling it with a vibrant mixture of glitter, oil, and water.

Learn more: Anti-Gravity Galaxy in a Bottle

4. Pool Noodle Marble Run

The pool noodle marble run gravity experiment is a fun and engaging way to teach students about the properties of gravity and motion.

In this experiment, students will create a track made from pool noodles and other materials to guide a marble as it travels from the top of the track to the bottom.

Learn more: Make a Pool Noodle Marble Run for Kids

5. Gravity Water Cup Drop

The water cup drop experiment teaches students about the laws of gravity and the effects of air resistance on falling items in a simple yet entertaining way. Students will perform this experiment by dropping a cup of water from a height and watching it fall.

6. Balloon Gravity Experiments

A creative and entertaining way to teach students about the force of gravity and its effects on objects is through the balloon gravity experiment.

By trying out these experiments, students can improve their problem-solving and critical-thinking skills while also learning more about the fundamentals of science.

7. DIY Balance Scales

Making your own balancing scales is a creative and engaging approach to introduce pupils to the ideas of stability and balance. Students can improve their sense of balance and coordination by carefully arranging the objects in this activity and adjusting their position and orientation.

Learn more: DIY Balance Scales

8. How to Make a Bottle Rocket

Making a bottle rocket for a gravity experiment is a fun and educational approach to teach students about the laws of physics and how gravity affects moving things. Students will use a plastic bottle, water, and pressured air to design and build a rocket during this project.

Learn more: How to Make a Bottle Rocket

9. Parachute Egg Drop Experiment

A fun and instructive technique to teach students about the fundamentals of physics and the science of aerodynamics is to try the parachute egg drop experiment. Students will design and build a parachute for this project.

This activity is a great bonus to any scientific curriculum because it is suited to different age groups and ability levels.

Learn more: Parachute Egg Drop Experiment

10. Putting Together the Gravity 

Putting together the gravity experiment is an exciting and educational way to teach students about the fundamental principles of physics and gravity.

In this experiment, students will design and create a setup that demonstrates the effects of gravity on different objects.

Learn more: Putting Together the Gravity

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Science Experiments for Kids: Learning About Gravity

Up, up, and away: fun and easy gravity experiments for kids.

Table of Contents

Amaze your friends and family with a science show. Ask your audience to predict the outcome of each of these easy science experiments about gravity .

All objects on Earth are pulled toward the planet’s center by the force of gravity. Gravity is the force that makes a basketball swish through a hoop. Gravity is the force that makes your glass of juice crash to the floor when it slips out of your hand. Gravity is the force that keeps your feet on the ground when you go for a walk. As Judy Breckenridge points out in Simple Physics Experiments with Everyday Materials, “Without gravity we would all float off into outer space.” Hooray for gravity!

In this post, we will share some of the best gravity experiments that you can do with your kids, using everyday materials that you can find at home. From balloon rockets to pendulum painting, these experiments will keep your kids entertained and educated all at once. Get ready to inspire your little ones with the wonder of science!

Quick Introduction to Gravity

Gravity is the force by which a planet or other body draws objects toward its center. The force of gravity keeps all of the planets in orbit around the sun . Earth’s gravity is what keeps you on the ground and what makes things fall. It’s what holds the atmosphere in place so we can breathe and it’s what allows us to use rockets to launch into space.

Gravity is a fundamental force of nature that is present everywhere in the universe. It is what gives objects weight and is responsible for the motion of planets, stars, and galaxies. Without gravity, the universe as we know it would not exist.

Understanding the basics of gravity is important for many areas of science, including physics, astronomy, and engineering. By conducting simple gravity experiments, kids can learn about this fascinating force of nature in a fun and engaging way. From exploring how gravity affects different objects to create their own mini-gravity wells, there are many exciting experiments that kids can do to learn more about this fundamental force.

Science Experiment: Dropping objects of different weights

Experiment 1: Dropping objects of different weights is a classic gravity experiment that teaches kids about mass and gravity. All you need for this experiment are a few objects of different weights, like a feather, a rock, and a rubber ball, and a place to drop them from, like a balcony or a staircase.

Start by asking your child what they think will happen when they drop each object. Will the heavier object fall faster or slower than the lighter object? Then, drop each object one by one and observe what happens.

You’ll find that all objects fall at the same rate, regardless of their weight. This is because gravity pulls all objects towards the earth at the same acceleration rate , which is 9.8 meters per second squared. You can explain this to your child by saying that the earth’s gravity pulls all objects towards it with the same force, so they all fall at the same rate.

You can also ask your child to try dropping the objects from different heights and see if that affects the way they fall. This will give them a better understanding of how gravity works and how it affects objects. This experiment is a great way to introduce your child to science and to help them understand the world around them.

Science Experiment: Making a gravity well

A gravity well is a concept that is used to represent the way gravity affects the path of objects in space. In this experiment, your child will learn how gravity works by creating a visual representation of a gravity well.

Materials needed:

• A large, flat container (such as a baking tray)
• A small ball (such as a marble)
• Food coloring (optional)

Instructions:

• Pour a thin layer of flour into the flat container, making sure it covers the entire surface.
• Place the small ball in the center of the container.
• If desired, add a few drops of food coloring to the flour around the ball.
• Use your fingers to gently press down on the flour around the ball, creating a depression in the flour. The depression should be deepest around the ball and gradually become shallower as you move away from the ball.
• Observe how the ball remains in the center of the depression you created in the flour. This is because the flour represents the fabric of space-time and the ball is pulled towards the center by the force of gravity.

To take the experiment further, you can try adding more balls to the container and observe how they behave differently depending on their mass and distance from the center of gravity well. This experiment is a great way to introduce your child to the fascinating concept of gravity and spark their curiosity about the world around them.

Science Experiment: Magnets to simulate gravity

Using magnets to simulate gravitational pull can be a fun and interactive way to teach kids about gravity. In this experiment, you’ll need a few simple materials such as a magnet, paper clips, and a thin piece of string.

First, tie the string to the magnet and then attach a few paper clips to the other end of the string. Next, hold the magnet above one of the paper clips and release it. You’ll notice that the paper clip is attracted to the magnet and will follow it as it falls. This is similar to how gravity works, as objects with more mass are attracted to each other.

You can also use this experiment to show how different objects with varying masses will be affected by gravity. Try attaching different objects to the string, such as a feather, a coin, and a small toy car. You’ll notice that the magnet has a stronger pull on the coin and car due to their greater mass, while the feather will not be affected as much because it has less mass.

This experiment is a great way to introduce kids to the concept of gravity in a fun and interactive way. It can also be a starting point for further discussions about the laws of physics and the universe around us.

Science Experiment: Making a simple pendulum

Making a simple pendulum is a fun and easy way to learn about gravity and motion. For this experiment, you will need a few simple materials:

• A piece of string or thread
• A small weight, such as a paperclip or washer
• A sturdy surface to attach the string

To make your pendulum, tie the string around your weight and attach the other end to your sturdy surface. You can use a table, a chair, or any other surface that won’t move around too much.

Once your pendulum is set up, give it a gentle push to set it swinging. Watch how it moves back and forth, and notice how the speed and direction of the pendulum change.

To make your experiment even more fun, try changing the length of the string or the weight of the pendulum. How does this affect the way the pendulum moves? Can you predict how the pendulum will behave based on these changes?

Making a simple pendulum is a great way to introduce kids to the concept of gravity and motion. Plus, it’s a fun and easy experiment that can be done with materials you probably already have at home.

Science Experiment: Gravity and Air Resistance

Before performing this experiment, show your audience a shoe and a flat piece of notebook or copy paper. Explain that you will be dropping both objects from the same height. Then ask your audience these questions:

• Who thinks the shoe will hit the floor first?
• Who thinks the paper will hit the floor first?
• Who thinks both objects will hit the floor at the same time?

Experiment:

• Hold the shoe in one hand and the paper in the other.
• Hold both objects high in front of you at equal heights.
• Release both objects at the same time.

Observation: The shoe hits the floor first.

Explanation: Because of the paper’s shape, its fall is slowed by air pushing up against its under-surface – this slowing effect is called air resistance.

Science Experiment: Effect of Gravity on Plant Growth

One of the most interesting aspects of gravity is its effect on living organisms. In this experiment, we’ll be looking at how gravity affects plant growth.

To start, you’ll need to gather some materials. You’ll need:

• 2 identical plants
• 2 identical pots
• Begin by filling both pots with soil and planting one of your plants in each pot.
• Water them both thoroughly and place them side by side in a sunny location.
• Now comes the fun part. Take one of the pots and place it on its side. This will cause the plant inside to be growing at a 90-degree angle to the ground. Leave the other pot standing upright.
• Over the next few weeks, observe the growth of both plants. Measure their height using the ruler and take note of any other differences you can see.

What you should find is that the plant growing at a 90-degree angle to the ground will grow differently than the plant growing upright. This is because gravity plays an important role in how plants grow. The plant growing on its side will have to work harder to grow against the pull of gravity, resulting in a different growth pattern than the one growing normally.

This experiment is a great way to teach kids about the effects of gravity on living organisms and can lead to further discussions about how gravity affects everything from trees to humans. Have fun experimenting!

Science Experiment: Gravity and Weight

Before performing this experiment, show your audience the shoe and the piece of paper crumpled into a ball. Explain that you will be dropping both objects from the same height. Then ask your audience these questions:

• Who thinks the paper ball will hit the floor first?
• Hold the shoe in one hand and the paper ball in the other.

Observation: The shoe and the paper ball hit the floor at the same time.

Explanation: Even though the earth exerts more pull on a heavier object, a lighter object experiences a greater degree of acceleration, meaning that it moves at a greater speed. Consequently, objects of different weights fall at the same rate when other forces such as air resistance are not a factor.

Science Experiment: Center of Gravity

Now it’s time for audience participation in your science show. Ask for volunteers for each of these exercises involving the center of gravity:

Pick up a penny

Ask a volunteer to stand against a wall with his feet together, heels pressed against the wall. Place a penny about one foot away on the floor in front of him. Ask him to pick up the penny without moving his feet or bending his knees. Can he do it?

Lift your left foot

Ask a volunteer to stand with her right side against a wall, pressing her right foot and cheek against it. Instruct her to lift her left foot off the floor. Can she do it?

Jump forward

Ask a volunteer to bend forward and grab his toes, keeping his knees slightly bent. Tell him to jump forward without letting go of his toes. Can he do it?

Ask a volunteer to sit in a straight-backed chair. Tell her to keep her back straight, her feet flat on the floor, and her arms folded across her chest. Then ask her to stand up. Can she do it?

Observation: Because all of these tasks restrict the center of gravity, it’s almost impossible for a person to perform any of them.

Explanation: As far as gravity is concerned, the weight of an object is concentrated at a single center point. The center of gravity for an object with a regular shape – the Earth, for example – is located at its geometric center. However, in irregularly shaped objects – the human body , for instance – the center of gravity moves around. If you try to shift too far away from your center of gravity, you’ll lose your balance.

Share Fun Science Experiments With Family and Friends

Learning new things about the world around you is fun and exciting. It’s even more fun when you share your discoveries with your family and friends. Gravity is just one of the interesting forces of nature – there are many more to explore and share.

Final thoughts on teaching kids about gravity

Gravity is a fascinating concept that has been studied and explored by scientists for centuries. Teaching kids about gravity can be a fun and engaging way to introduce them to the wonders of science and the natural world around them.

By conducting simple experiments and activities, kids can learn about the basic principles of gravity and how it affects the world around us. From dropping objects of different weights to observing how objects fall at the same rate, there are endless ways to explore this fascinating force.

Not only can teaching kids about gravity be fun, but it can also help to develop their critical thinking skills, problem-solving abilities, and scientific knowledge. By encouraging kids to ask questions and explore the world around them, we can inspire a love of learning and an appreciation for science that can last a lifetime.

Teaching kids about gravity can be a fun and rewarding experience for both children and adults alike. By providing opportunities for hands-on exploration and discovery, we can help kids develop a lifelong love of science and learning. So, let’s get started and see where the wonders of gravity take us!

• Bardhan-Quallen, Sudipta. Championship Science Fair Projects . NY: Sterling Publishing, 2004.
• Breckenridge, Judy. Simple Physics Experiments with Everyday Materials . NY: Sterling Publishing, 1993.
• Cobb, Vicki. Bet You Can’t! NY: Lothrop, Lee & Shepard Books, 1980.

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27 Gravity Activities For Elementary Students: Experiments And Resources

December 28, 2023 //  by  Alison Vrana

The concept of gravity is one of the core concepts that are taught in elementary science classes. Students also need to be able to understand how gravity works in order to move on to upper-level science classes like physics. The lessons, activities, and gravity science experiments below teach kids how gravity and motion work in tandem. These lessons are aimed at creating life-long science interests so check out our 27 amazing activities that’ll help you do just that! 

1. Watch “How Gravity Works For Kids”

This animated video is perfect to start a unit. The video explains gravity in simple science vocabulary that students can understand. As an added bonus, this video can be shared with absent students so they don’t get behind.

Learn More: YouTube

2. DIY Balance Scales

This science activity can be used to teach motion and gravity at any age. Using hangars, cups, and other household items, students will have to determine which items balance and which items are heavier than others. Teachers can then talk about the relationship between weight and gravity.

Learn More: Go Science Kids

3. Egg Drop Experiment

The egg drop experiment is a student-friendly science activity for elementary students. There are different ways to complete the experiment which include building a paper cradle or using a balloon drop to protect the egg. Kids will love trying to protect their eggs as they’re dropped from a high vantage point.

Learn More: Science Sparks

4. Gravity Drop

This gravity drop activity is super simple and requires very little prep from the teacher. Students will drop different items and test how each item falls. 

Learn More: Stay At Home Educator

5. Marble Maze

The marble maze is a hands-on science investigation task that will teach kids about gravity and motion. Kids will build different mazes and observe how the marble travels through the maze based on different ramp heights.

Learn More: Investors Of Tomorrow

6. DIY Gravity Well

The DIY gravity well is a quick demonstration that students can complete at a learning center or as a group in class. Using a strainer, students can observe how an object travels from the top to the bottom. This great lesson also doubles as an opportunity to teach about speed.

7. Superhero Gravity Experiment

Kids will love combining their favorite superheroes with learning. In this experiment, children work in partners to experiment with how to make their superhero “fly”. They learn about different heights and textures to see how gravity helps the superhero move through the air.

Learn More: Teaching Ideas

8. Anti-Gravity Galaxy in a Bottle

This activity demonstrates how gravity and water work. Teachers can also connect this demonstration to the idea of friction. Students will make an “anti-gravity” galaxy in a bottle to see how glitter floats in the water.

Learn More: One Little Project

9. Gravity Book Read-aloud

Reading aloud is a great way to start the day or start a new unit with your elementary learners. There are several helpful books about gravity that kids will love. These books also explore science concepts like friction, motion, and other core ideas.

Learn More: CBC Public Library

10. Balancing Stick Sidekick Activity

This is a super simple activity that helps introduce kids to the concepts of balance and gravity. Teachers will give each student a popsicle stick, or a similar item, and have them try to balance the stick on their fingers. As students experiment, they will learn how to balance the sticks.

Learn More: Hands-On As We Grow

11. G is for Gravity Experiment

This is another good activity to introduce the concept of gravity in your primary classroom. Give your students a bunch of different objects of varying weights and sizes. The students will then drop them from a designated height whilst timing the drop with a stopwatch. What a fun way to learn how gravity relates to mass!

Learn More: PBS

12. Large Tube Gravity Experiment

This activity is a fun idea to introduce students to friction, motion, and gravity. Kids will experiment with how to get a car to travel faster down the tube. As students try different tube heights they will record real-time student data for their experiment.

13. Splat! Painting

This art lesson is a simple way to incorporate a cross-curricular lesson that teaches gravity. Students will use paint and different objects to see how the paint creates different shapes with the help of gravity.

Learn More: Fun A Day

14. Gravity Defying Beads

In this activity, students will use beads to demonstrate the concepts of inertia, momentum, and gravity. The beads are a fun tactile resource for this experiment, and as an added bonus, they make noise which adds to the appeal of a visual and auditory lesson.

Learn More: The Chaos And The Clutter

15. The Great Gravity Escape

This lesson is good for upper elementary students or advanced students who need more enrichment. The activity uses a water balloon and string to see how gravity can create an orbit. Teachers can then apply this concept to space crafts and planets.

Learn More: Teach Engineering

16. Center of Gravity

This lesson requires only a few resources and little preparation. Students will experiment with gravity and balance to discover different items’ centers of gravity. This hands-on experiment is super simple but teaches kids a lot about core gravity concepts.

Learn More: Teacher Source Blog

17. Gravity Spinner Craft

This gravity craft is a great lesson to wrap up your science unit. Kids will use common classroom resources to make a spinner that is controlled by gravity. This a fun way to bring science concepts to life for young learners.

Learn More: Teach Beside Me

18. The Spinning Bucket

This lesson shows the relationship between gravity and motion. A strong person will spin a bucket full of water and students will see how the motion of the bucket affects the trajectory of the water.

Learn More: Sciencing

19. Hole in the Cup

This activity demonstrates how objects in motion together stay in motion together. Teachers will use a cup with a hole at the bottom filled with water to demonstrate how the water will come out of the cup when the teacher is holding it because of gravity. If the teacher drops the cup, the water won’t spill out of the hole because the water and the cup are dropping together.

20. Water Defying Gravity

This is a cool experiment that seemingly defies gravity. All you need is a glass filled with water, an index card, and a bucket. The lesson will demonstrate how gravity affects objects differently to create the illusion of anti-gravity.

Learn More: Kidz Search

21. Gravity Painting

This crafty activity is another great way to incorporate gravity into a cross-curricular activity. Students will use paint and straws to create their very own gravity painting. This is perfect for 3rd- 4th-grade science class.

Learn More: Curiodyssey

22. Bottle Blast Off!

Kids will love building their own rockets using just air to launch them. Teachers can help students understand how rockets are able to travel into the sky despite gravity. This lesson requires a lot of student direction, but they will remember what they learn for a lifetime!

Learn More: Exploratorium

23. Falling Feather

5th-grade science teachers will love this experiment. Students will observe how objects fall at different accelerations if resistance in the air is present versus falling at the same acceleration if there is no resistance.

24. A Pencil, Fork, and Apple Experiment

This experiment uses just three objects to demonstrate how weight and gravity interact. Students will be able to visualize how the objects are able to balance because of gravity. This experiment is best conducted if the teacher demonstrates it at the front of the class for all to see.

Learn More: Kid Minds

25. Watch 360 Degree Zero Gravity

This video is great to incorporate into a gravity unit. Students will love seeing how zero gravity affects people and what astronauts look like in space.

26. Magnetism and Defying Gravity

This science experiment uses paper clips and magnets to help students determine if magnetism or gravity is stronger. Students will use their observation skills to determine which force is stronger before stating why.  

Learn More: Education

27. Textured Ramps

In this cool science activity, students will use different ramp heights and the variable of ramp texture to see how gravity and friction affect speed. This is another experiment that’s great for science centers or as a whole class demonstration.

Learn More: Teach Junkie

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Simple Gravity Experiments

The Physical Factors Affecting Parachutes

Gravity is a fundamental part of nature that keeps our feet planted firmly on the ground. This unseen force is responsible for tides, keeping Earth from careening into the darkness of space, and for causing food to hit the kitchen floor when it slips from your hand. Though invisible, gravity's effects can be observed by performing simple and easy-to-do experiments.

Galileo's Experiment

Named after the scientist who is popularly believed (though not verified) to have performed this experiment, it involves taking two objects of different sizes and weights and dropping them to see which one hits the ground first. As the Earth's gravity affects objects at the same rate regardless of their weight, without air resistance the objects should hit the ground at the same time. Try this with different objects with varying weights and air resistance and observe its effects.

The Spinning Bucket

Showing the relation between motion and gravity, for this experiment you need a bucket with water and someone with a strong arm to spin it. In theory, when the bucket turns upside down the water should come spilling out as gravity pulls it downwards. Spinning it fast enough, the water tends to keep going in a straight line, counteracting the pull of gravity and thus wedging it to the end of the bucket, preventing the natural pull of gravity from spilling the water. This is why this effect, called “centrifugal force” is often referred to as artificial gravity.

The Hole in the Cup

For this experiment you need a paper cup and some water. Poke a hole in the cup and cover it with a finger; fill the cup with water. Take your finger from the hole and notice the water spills out. Though gravity pulls down both objects, only water moves freely (because you're holding the cup); thus, gravity forces the water out. Fill the cup again and drop it to the ground. Now that both objects are free to move, they drop at the same speed so the water isn't forced out of the hole.

Center of Gravity

A center of gravity experiment can be done quite easily; all that is required is a pencil or pen and your finger. Try to balance the pen at different positions on your finger until you reach the point where it doesn't fall off. This is the center of gravity of the pen, the point in which its weight averages out and, if it were in a weightless environment, the point at which it can freely rotate. Put on the cap and try to balance it again. As the weight of an object changes, so does its center of gravity.

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• Kids Science Experiments: Spinning Bucket of Water
• Discovery Channel: Gravity Gets You Down
• NASA: Center of Gravity

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Find Your Next Great Science Fair Project! GO

Rotate your device to experience this experiment

01 gravit y/.

Observations

How do celestial bodies warp the fabric of space-time and interact with each other?

ABOUT THIS EXPERIMENT

We tend think of gravity as a force of attraction, but it’s also been described as a curvature of space-time in the presence of mass. This National Science and Technology Medals Foundation interactive invites you to bend the fabric of space-time and observe the resulting gravitational forces. By adjusting the variables of mass, distance, and velocity, you can trigger orbits, collisions, and escape velocities in space.

The National Science and Technology Medals Foundation celebrates the amazing individuals who have won the highest science, technology, engineering, and mathematics award in the United States.

Jeremiah P. Ostriker

Studied the gravitational effects of dark matter.

John A. Wheeler

Popularized Einstein’s theory of relativity after WWII.

Edward Witten

Charted the topology of space-time.

Robert H. Dicke

Predicted the discovery of the Big Bang echo.

Allan R. Sandage

Discovered the first quasar.

See All Laureates in Theory & Foundations

Your universe has reached critical mass and collapsed. Fascinating!

Learn more about the pioneering scientists and thinkers behind this experiment at nationalmedals.org

Here are a few to check out:

Falling for Gravity

Calculate the acceleration of gravity using simple materials, a cell phone, and a computer to record, watch, and analyze the motion of a dropped object.

• Two-meter measuring tape or two meter sticks
• Masking tape
• Small, cheap, rugged flashlight
• Towel, carpeting, or other soft material for the dropped flashlight to land on
• Digital camera with video capability (the HD camera on a phone should work fine)
• Computer with a program that lets you play videos frame by frame (not shown)
• Pencil and paper to record data (not shown)

• Locate a wall with a non-reflective surface. This Snack will not work in front a whiteboard or window.
• Tape the two-meter measuring tape to a flat wall. Position the measuring tape so that the 0 cm mark is at the top and the remainder hangs straight down. (If using meter sticks, tape and stack the two sticks together to make a total length of two meters.)
• Directly below your measuring tape, place a towel, carpeting, or other material that will soften the impact of dropping the flashlight on the floor.
• To make the measurements more visible, add extra marks on pieces of masking tape and stick them next to the measuring tape every 5 or 10 centimeters.

Collect your data

Have one partner stand next to the measuring tape. Turn on the flashlight and point it upwards. Make sure your flashlight is on a non-blinking setting. Place the light as close to the 0 cm mark as possible and against the measuring tape. If possible, use only one finger to hold the flashlight still until the time of release. Have someone else film the drop with a digital camera (in HD at standard 30 frames per second).

Check your video to make sure you got the shot. Digital video is easy to erase and reshoot. Redo it if you didn’t get a clear view of your flashlight’s light falling straight down. Transfer your video file to a computer.

Record your data

Make a table with two columns to record your data. Label the columns “Time in seconds” and “Distance in meters.” (See the sample table below.)

Time Data: Since your camera records 30 frames a second, each frame represents only 1/30 of a second, or about 0.033 seconds. That means each frame will add an additional 0.033 seconds.

Distance Data: In your video player, find the frame just before your flashlight drops. (Note that frame-by-frame players usually let you move forward or backward via arrow keys. The frame you’re now at is time 0s and distance 0m.)

Now, step by step, record the distance in meters dropped and the corresponding time of the flashlight’s fall. Watch the screen closely. Notice that, during the first few steps, the flashlight doesn’t fall very much.

If your flashlight leaves a streak of light, only record the location at the bottom of the streak (the streak is a 1/30 th  of a second record of the light's fall).

Calculate the acceleration due to gravity

Acceleration describes how fast the rate of something changes.

Acceleration = ( V final – V initial ) / the time to make this change

Here’s an example using our data (see the table above): V initial is the flashlight’s velocity just before it’s dropped, or 0 m/s; V final is the velocity of the light at the end of the drop.

In our case, at time 0.297 to 0.33 s (time = 0.033 s), the distance traveled is from 0.4 m to 0.51 m (distance = 0.11 m).

V = distance / time

So, V final = 0.11 m / 0.033 s = 3.33 m/s

The time it takes to make that change is 0.33 s

Acceleration = (3.33 m/s – 0 m/s) / 0.33 s = 10 m/s 2

Use your own data to calculate the acceleration of the flashlight you drop.

In your own experiments, you can collect data from shorter or longer distances.

$$\text{Acceleration} = \frac{3.33 \text{m/s} - 0 \text{m/s}}{0.33 \text{s}} = 10 \text{m/s}^2$$

Gravity is a force that draws objects to one another. In this case, the objects are the flashlight and the earth. This fundamental interaction of nature causes objects like the flashlight to move toward the earth faster and faster.

Look at your data. You might notice that the distances between successive time intervals increases. This also means the object’s velocity is increasing, and increasing velocity is known as acceleration. You might have heard a car commercial use the phrase “Zero to sixty in five seconds,” or some such thing. That means the car went from one velocity to another in a certain period of time—that’s acceleration!

Things accelerate toward the earth at a constant rate. Your data should show that this rate is about 9.8 meters per second per second, or 9.8 m/s 2 . Scientists, engineers, teachers, and students also know this constant as, simply, g .

Graphing is a great way to see what’s going on with your data. Try plotting distance vs. time.

Is your graph a straight line? Is it a curve?

It should be a curve with the formula: d = 1/2 g t 2 ​. The graph of our sample data is shown below.

Put an object on a scale. Is it moving? Although it doesn’t look like it, your object is actually accelerating towards the earth. The scale’s pan is pushing again your object and forcing it from moving downward. The weight you read on your device is a result of the object’s mass and g .

Try doing this activity again, but drop lightweight objects with lots of surface area, such as coffee filters or feathers, and see how the results differ. Although g is still at work here, air resistance also plays a role.

See this Snack in action in this video .

Related Snacks

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15+ Preschool Science Experiments that Explore Gravity

August 17, 2016 by Sheryl Cooper

Last Updated on July 22, 2024 by Sheryl Cooper

Inside: Explore gravity with these 7 fun preschool science experiments ! Activities that include pushing, throwing, and falling – all hands-on and fun!

Have you noticed how preschoolers are fascinated by things that move? Whether it’s pushing, throwing, or falling, they are very into it!

So why not tap into this interest?

Here are 7  fun preschool gravity experiments that you can add to your classroom or home activities , or for weekend fun.

 When talking about gravity with preschoolers, we keep it simple.

During our morning meeting or circle time , we demonstrate what happens if we drop an item.

We notice that it went down instead of up.

We can then try a gravity experiment during small groups, noticing that if we alter the movement or materials, things change.

This is basic and yet fascinating for this age group!

Defy Gravity  – This super cool activity is easy to make with paperclips and magnets. (Buggy and Buddy)

Drip Painting – Discover what happens when watercolors are dropped from the top of a vertical surface.

Galaxy in a Bottle  – The glitter doesn’t fall down, but instead rises as it settles. Crazy! (One Little Project)

Gravity Splatter Art – What happens when you drop something with paint on it?

Exploring Gravity with a Tube – Why does the position of the tube change the speed of the car? (HOAWG)

Exploring Gravity with Balance – Learn how to make a craft stick stand up right on a chopstick. (Rookie Parenting)

Gravity with a Pendulum  – Learn about the forces of motion and gravity by placing paint in swinging pendulum. (Innovation Kids Lab)

Pool Noodle Gravity Play – Explore gravity and slope by making your own pool noodle marble run. (Little Bins for Little Hands)

Ball Dropping Experiment – Drop different types of balls and see which one hits the ground first. (Inspiration Laboratories)

Apple Races – Explore gravity, motion, slopes, and more as they are rolled down plastic rain gutters. (Little Bins for Little Hands)

Water in a Jar Activity – How can you stop water from coming out of a glass when it’s turned upside down? (The Homeschool Scientist)

Bottle Rocket Launch – After making your own bottle rocket, make it launch by pumping air into it. (Science Sparks)

Which One is Heavier – Make your own balance scale and find different objects to weigh. (Go Science Kids)

Parachute Egg Drop Experiment – Learn about gravity and air resistance while dropping an egg using a parachute. (Science Sparks)

Center of Gravity Balancing Activity – This Cat in the Hat inspired activity involves balancing objects on a single point. (Preschool Pool Packets)

Exploring the Effects of Speed – Learn how speed has an effect on the gravitational pull on an object. (JDaniel4’s Mom)

More science for preschoolers:

Rainbow Science Activities

Winter Science Activities

15 Space Activities

Check out our favorite science toys and materials:

More science resources:

Hands-On Preschool STEM Activities

Science Activities that Explore Gravity

10 Science Experiments Preschoolers Love

Check out our science pin board for more fun!

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About Sheryl Cooper

Sheryl Cooper is the founder of Teaching 2 and 3 Year Olds, a website full of activities for toddlers and preschoolers. She has been teaching this age group for over 25 years and loves to share her passion with teachers, parents, grandparents, and anyone with young children in their lives.

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Parachute Egg Drop Experiment – Gravity and Air Resistance

July 19, 2019 By Emma Vanstone 9 Comments

This fun parachute egg drop experiment is a great demonstration of the forces acting on parachutes. If you drop something, it falls to the ground. This is because it is pulled by the gravity of the Earth. You’ll notice that some things drop faster than others. This is because of air resistance . Try dropping a piece of paper and a lego brick. Which drops the fastest?

We are going to try dropping an egg on its own, dropping an egg attached to a parachute and an egg in a basket under a balloon.

Egg Drop Experiment

How to make an egg parachute

What you need to make a parachute.

• Bin bag/ plastic sheet/paper or other flat material.
• 4 pieces of string
• sellotape or masking tape
• 3 eggs ( we boiled ours )

Parachute Instructions

• Lay the bin bag out flat and cut out a big square.
• Make a hole in each corner, thread a piece of string through it and tie a knot.
• Tie all 4 pieces of string together and sellotape the egg to the bottom

Make Your Own Air Balloon

Air balloon materials.

• Cardboard made into a basket shape or a small plastic container
• Balloon blown up
• 4 pieces of String

Air Balloon Instructions

• Sellotape some string to your balloon and attach the basket.
• Place the egg in the basket

Drop an egg on its own, the egg in the basket and the egg in the parachute from somewhere high up. Make sure an adult is around to help with this part.

Gravity and Air Resistance Explained

If you tried dropping paper and a lego brick or similar, the paper should have dropped to the floor more slowly than the brick. This is because the paper has a larger surface area, so has to push against more air as it drops, which means the air resistance is greater, and it drops more slowly.

An egg dropped without anything to slow it down will fall fast and break; the parachute and balloon add air resistance, slowing the fall and stopping the egg from breaking.

We also found that the parachute fell much more slowly than the balloon. This is because the parachute has a larger surface area than the balloon, and so slows the descent of the egg more.

If we dropped a hammer and a feather, we would expect the hammer to fall fastest; however, if we did this on the moon where there is no air resistance, they would hit the ground at the same time!

How do Parachutes Work?

As we explained above, two forces act on an object as it falls. Gravity pulls the object down, and air resistance slows the fall.

Parachutes are used to slow the fall of an object by increasing air resistance which reduces the effect of gravity!

More parachute investigation Ideas

Record the time taken for all three to drop and see how much slower the parachute is.

Try our experiments you can make fly .

Experiment with different sizes of parachutes and see which drops more slowly.

Don’t forget to try our collection of easy ideas for learning about forces too.

In This IS Rocket Science we made parachutes with coffee filters which was great fun and you can experiment with different sizes and shapes.

If you liked this science experiment you’ll LOVE my book This IS Rocket Science, which has 70 space themed science experiments for kids!

This post was originally published in 2011 and updated July 2019

Last Updated on March 14, 2023 by Emma Vanstone

Safety Notice

Science Sparks ( Wild Sparks Enterprises Ltd ) are not liable for the actions of activity of any person who uses the information in this resource or in any of the suggested further resources. Science Sparks assume no liability with regard to injuries or damage to property that may occur as a result of using the information and carrying out the practical activities contained in this resource or in any of the suggested further resources.

These activities are designed to be carried out by children working with a parent, guardian or other appropriate adult. The adult involved is fully responsible for ensuring that the activities are carried out safely.

Reader Interactions

September 11, 2011 at 8:49 am

Fab. Really well explained!

September 14, 2011 at 10:11 pm

Thank you. xx

October 28, 2013 at 12:44 am

cool video but it didn’t answer my question

September 11, 2011 at 3:03 pm

You always make science fun!

September 14, 2011 at 10:10 pm

Thank you, we do try!

September 11, 2011 at 7:59 pm

That is cool. Did the egg break when you did that? Nevermind I saw the answer when I reread it.

THanks for linking up this week!

Thank you for hosting such a great link up. x

September 14, 2011 at 2:16 pm

Love how you make science fun and bring it into the home… Did you know I did Physics A-Levels? Well, this will come in handy with my kids! 🙂

Thanks for sharing on Kids Get Crafty!

June 10, 2016 at 9:08 am

This website is very good in my school all the year 5 used it to make a paacute for there topic ‘Wacky races’ thank you for making it

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Hands-On Superhero Gravity for Kids

I teach a lot of science at school to young kids. They love learning about the world around them and gaining an understanding of how things work. I love finding ways to teach young children about big scientific concepts in a way that makes sense to them. Today our topic is gravity for kids!

I wanted to find some gravity experiments for kids that were science based, but also engaging. The children that I teach love talking about superheroes and had even been learning about them in class.

So, for science, I decided to mix our gravity lesson with their interest in superheroes. I used different superhero figures to show everyone a bit about gravity for kids!

There are only a few simple materials that you need for this gravity experiment. A link to purchase the materials is included at the bottom of this post.

• Small Superhero Figures
• Plastic Straws
• String/Yarn/Fishing Line

I prepared the materials ahead of time because I needed to use hot glue.

Cut each straw to be roughly an inch, or a few centimeters.

I then put a line of glue on the superheroes back and stuck the straw down and made sure that it was secure. (As pictured)

Next, I threaded string through the straw. The string you use needs to be quite long, depending how far you want your superhero to fly. I made enough so that I could give each pair of children a superhero with a string attached.

I also kept one superhero for myself to use later for my gravity for kids demonstration. The string on my superhero was really long!

Once your materials are ready, you can start the experiment with children.

Gravity for Kids Experiment Steps

I like making experiments as hands-on as possible with kids. I find when children are given the opportunity to explore the materials and test them out on their own, they are more likely to remember and learn from the activity.

Start by pairing children up and giving each pair a superhero figure that is attached to a string. The string that I used for the children was only a few meters long.

I started by giving each pair a superhero figure that was attached to a string.  Originally I used yarn (as pictured).  However, I later changed it and used fishing line.  There is less friction with the fishing line and the superhero ‘flew’ better.

In pairs I had each child hold one end of the string and move apart from each other so that the string was tight.  They both started holding the string up as high as they could. One child then moved their end of the string down to the ground.

Children quickly noticed that their superhero would ‘fly’ when one end of the string was lifted higher than the other.

I then introduced the word gravity. Children noticed that their superhero would always slide down towards the ground.

They were encouraged to move the string up or down in an attempt to make their figure move, or ‘fly’. 

I gave children some time to explore and experiment with their superheroes and trying to make them fly.

Whole Group Gravity for Kids Experiment

After partners experimented with their superhero, we then took did the experiment together.

Take one end of the long string that your superhero is attached to and move to a higher place. I climbed our playground equipment as children watched from below.

To add to the height, I tied one end of my string to a long stick so that I could lift the superhero even higher above my head.

As I stood at a higher point, I had a child at the bottom with the other end of the long string.

Based on their own experimenting with the string and superheroes, children all thought of a hypothesis for what they thought was going to happen when I let go of my superhero.

I used the stick to help easily raise the string to an even higher point. I then let go!

Because of gravity, the superhero “flew” down towards the children at the bottom. He glided from a higher, to lower point.

I then asked my volunteer at the bottom, holding the string, to send my superhero back up top to me. Despite several attempts, we all concluded that it was gravity that pulled our superhero down, but it would not help send it up.

This experiment serves as an easy introduction to gravity for young kids and a great way to get outside!

Gravity for Kids Extension Ideas

My students really enjoyed this activity and having a small superhero “fly” over them. I wanted to continue this enthusiasm and interest so there are a few extension activities you can try.

One thing that can make a difference with this experiment is the string or yarn you use. Thick, fuzzy yarn may cause a lot of friction and make your superhero not slide very well. You can compare yarn, wool, string and fishing line an any other material you have available to see which works best to help your superhero slide.

Testing out different strings could also teach kids about friction and the fact that although everything is pulled to the ground because of gravity different materials can play a role in the speed.

If you try out different strings you can also have some fun with it by racing the different superheroes. This way children will learn about gravity, but also friction. And the best part is, they will have fun as they are learning.

Although I did this experiment in a school setting, you can easily do it inside or outside at home. As long as one end of the string is higher children will clearly see that the superhero will slide down towards the ground, but never up.

That’s the basic idea that young children need to understand about gravity.

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81+ Science Experiments for Kids

Looking for more hands-on science experiments? Check out this collection of over 80 science experiments that you can try out today!

More Hands-On Teaching Ideas

Looking for more learning activities for kids at home or school? Below is a collection of my favourite, and most popular hands-on activities, from outdoor activities and building challenges to escape rooms and printables, I’ve got lots of ideas to keep kids busy and learning.

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3 Unique Gravity Experiments to Try with Your Kids

Simply put, gravity is the force of the earth that pulls objects towards its core, preventing them from floating off into space. For many adults, explaining the concept of gravity to a child can seem daunting. However, through the use of the following gravity experiments for kids, children will gain a better grasp of gravity’s role in our everyday lives while also having some fun!

Paperclip Gravity Experiment

Most gravity experiments don’t require many materials. For this experiment you’ll use:

• Paper clips

First, tie one end of a piece of string to a paperclip and tie the other end around the stick. Repeat twice more so that the stick has three paper clips attached. Hold the stick up in the air, allowing the paperclips hang freely. Tilt the stick back and forth.

As is demonstrated, Earth’s gravity is continuously pulling our bodies and the objects around us to its core. Even when the stick is tilted, Earth’s gravitational pull exerts its force on the paper clips pulling them straight down toward the Earth.

Gravity Water Drop

This next experiment requires just three items:

• A paper cup

On the outside of the cup near the bottom, poke a hole using a pencil. Placing a finger over the hole, fill the cup with water. Remove your finger from the hole. You should find that the water flows out of the cup in an even, steady stream (if the water is not quite flowing smoothly, try poking a new hole and refill the cup with water). Next, holding your finger over the hole, fill the cup once again with water. Drop the cup, removing your finger from the hole at the same time. You’ll find that as the cup falls, no water flows out of the hole.

When you first held the cup in the air and removed your finger, gravity pulled the water down towards the ground and water pressure forced it out of the hole. However, when the cup and water fell at the same speed, there is no water pressure. Without this force, the water remains inside the cup as gravity pulls both to the ground.

Galileo’s Experiment

• A sturdy chair
• Various household items

Gather items of differing weights and sizes, such as a ball, action figure or doll, and a balloon. Have your child stand on top of the chair while holding the items. One at a time, have your child drop each item from the same height. Keep track of how long it takes each item to reach the ground.

Though many believe that larger, heavier items will hit the ground first, this is not true. The rate of Earth’s gravitational pull on all objects is the same regardless of weight. Given the absence of air resistance, each object should reach the floor at the same time. Do your finding support this?

Testing the laws of gravity (or defying them !) can be done in a variety of hands-on, entertaining ways around the house and at school. Experiments for kids like those above are a great way to get kids learning and asking important questions about the world around them.

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Buggy and Buddy

Meaningful Activities for Learning & Creating

January 4, 2017 By Chelsey

Easy Science Experiments for Kids: Gravity Activity with Paperclips

This easy science experiment is a fun way to demonstrate the concept of gravity to young children. You’ll just need a few supplies, including paperclips and magnets, to take part in this cool science activity!

This activity correlates with NGSS: Disciplinary Core Idea PS2.B.

Follow our Science for Kids Pinterest board!

Here’s a fun way for young children to explore gravity. Kids will first observe how gravity is always pulling objects toward the Earth by using paperclips and string. Then the super cool part- children will use magnets to explore how gravity can easily be overcome by other forces- almost like defying gravity! (This post contains affiliate links.)

See it in Action!

Exploring gravity with young children.

Whenever I  invite my kids to participate in  science activities,  my main goal   is  NOT  for them to   master a set concept, but simply to allow them to explore the activity in their own way. Giving this freedom to children inspires them to make predictions and critically think about the world around them in a pressure-free setting.  

What exactly is gravity?

Gravity is a force that tries to pull two objects toward each other.  Earth’s gravity is what keeps you on the ground, what causes objects to fall, and is why the objects fall down rather than up!

Materials for Gravity Experiment

• Small dowel or stick
• Strong magnets (Use either neodymium magnets .5 inch or bigger or ceramic magnets .75 inch or larger. Regular craft magnets won’t work.)
• Metal ruler (or wooden ruler with tape)
• Blocks, books, or other material for stacking

Important: Not only are small magnets choking hazards, but magnet ingestions pose a serious threat to the health of children. NEVER leave any child unattended with magnets. Never allow any child under 3 to use magnets.

Directions for Gravity Experiment

1. Start by tying some paperclips to pieces of string. Then tie the string onto a small dowel rod or stick.

2. Lift up the dowel rod so the paperclips hang from the string.

• Which direction do the paperclips point?
• What happens if you tilt the stick? 

Theo was amazed to observe that no matter which way he tilted the stick or how steep an angle he tilted the stick, the paperclips always pointed right down at the ground!

We talked about how the Earth’s gravity is what holds us and other things to the ground.  The paperclips are being pulled toward the Earth by gravity, but they can’t fall because the string is holding them in the air. No matter which way we tilted the dowel rod, the paperclips were still being pulled straight toward the Earth by gravity.

Next we explored how gravity can easily be overcome by other forces using magnets.

3. Place three magnets along a metal ruler . (If you’re using a wooden ruler, you can tape the magnets to the top.)

4. Suspend the ruler from two stacks of blocks, books, or other materials. Be sure the magnets are facing down.

5. Take the paper clips and string off your dowel rod.

6. Take one paperclip and hold it until it’s just suspended below the first magnet. Tape the string in place onto the table (or whatever surface your activity is on). Do this with the other two paperclips.

7. After taping the strings in place below the magnets, remove the ruler and observe what happens. All the paperclips fall to the ground! We talked about why the paperclips were not going up into the air after we removed the magnets.

8. Put the ruler with magnets back above the paperclips. Slowly lift each paperclip toward each magnet until they are all suspended. The kids were very excited about this demonstration!

We talked about how the magnetic force between the paperclip and magnet were stronger than the pull of the Earth’s gravity on the paperclip, so the paperclip was able to remain in the air rather than fall back to the ground.

Lucy and I came up with other forces that seemed to defy gravity- like static electricity holding strands of hair straight up in the air or how the hot air in a hot-air balloon can lift people off the ground.

Want to go even further?

Even more activities about gravity to inspire creativity and critical thinking for various ages.

•  Use gravity to create this colorful art from Fun-a-Day!
• Explore how air resistance affects gravity in this activity from Science Sparks.
• Make some wooden ramps for toy cars and explore how different angles of the ramps affect the acceleration of the cars.
• Some children’s books about gravity: Gravity is a Mystery ,  The Day Katie McAvity Turned Off Gravity

All activities on Buggy and Buddy are activities I feel are safe for my own children.  Contact your child’s pediatrician for guidance if you are not sure about the safety/age appropriateness of an activity. Never leave your child unattended. The author and blog disclaim liability for any damage, mishap, or injury that may occur from engaging in any of these activities on this blog.

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Gravity Activities For Preschoolers

There are so many low or no-prep hands-on gravity activities that you can do with young kids to introduce this concept! We love easy preschool science activities !

Fun Ways To Demonstrate Gravity

Here’s my son at age 3, exploring a book filled with pictures of kids testing out gravity. Then, we had a blast jumping, falling, dropping, rolling, and pouring things together. I think he got the idea that what goes up must come down (unless it gets stuck)! Here are super quick ways to demonstrate gravity in 2 minutes.

• Pour water into a glass.
• Knock something (not breakable) off a table.
• Fall onto a bed or a pile of cushions.
• Push a toy car down a toy ramp (Hotwheels tracks).
• Toss a pile of socks in the air.

Gravity Activities For Kids

How do you explain gravity to young kids? You show them! Take a look at these playful, hands-on activities that get kids moving and explore how fun gravity is. My son loves anything gross motor involved, and gravity activities can incorporate lots of movement for young kids.

💡Get up and test gravity for yourself with a free gravity activity pack ! Share this information guide, quick activity, and gravity coloring sheet with your kids!

Some activities share an easy description to get you started, as they are meant to be low to no prep. In comparison, some activities have links to explore further how to do the activity!

💡 Note: While the concept of gravity is much more involved than the simple examples below, it’s just the right amount of information for our youngest scientists! For older kids, check out these gravity experiments !

Dropping Objects

Have kids drop various objects (e.g., balls, feathers, toys) from different heights and observe how they fall. Explain that gravity pulls objects down towards the Earth.

Feather and Coin Test

Place a feather and a coin side by side. Ask kids which one will hit the ground first when dropped. Demonstrate that they both fall at the same rate due to gravity.

Water Balloon Toss

Fill water balloons and play catch. Discuss how the balloons fall because of gravity pulling them downward.

Show how gravity affects us by performing jumping jacks, jumping on a trampoline, or simply jumping in place and feeling the force pulling us back to the ground.

Magnet Play

Use a magnet and a variety of metal and nonmetal objects to show how magnetic pull is stronger than gravity. Check out all sorts of fun magnet activities here .

Balancing Act

Use a ruler or stick to balance various objects on the edge. Talk about how gravity keeps them stable or causes them to fall. Check out our balancing apple or balancing animal activities to try this!

Paper Airplanes

Fold paper airplanes and see how gravity pulls them downward when thrown. make our paper airplane launcher here.

Rolling Race

Use toy cars or balls to race down ramps at different angles. Discuss how gravity influences their speed. Check out our ramps and friction activity for preschoolers or this fun apple race gravity demonstration.

Waterfall Experiment

Pour water down a sloped surface and watch it flow due to gravity. Build a water wall!

Floating and Sinking

Test different objects in a water basin to see which ones float (buoyancy) and sink due to gravity. Try this sink or float experiment!

Marble Run/Maze

Build a simple marble maze and observe gravity pulling the marbles through the tracks. Use paper towel tubes to create a marble coaster.

Helium Balloons

Compare regular and helium balloons to show how gravity pulls one down while the other floats up.

Quick explanation: Gravity is still pulling down the balloon but the special gas inside keeps is different than regular air so it keeps it floating instead. In fact, if you don’t tie down a helium balloon it will float away until the gas inside slowly leaks out.

Musical Chairs

Play musical chairs and discuss how gravity keeps everyone seated until the music stops.

Bouncing Balls

Show how gravity causes a ball to bounce back up after hitting the ground. Have fun tossing and bouncing different balls. See how you can incorporate this into gravity art below.

Fly Swatter Balloon Tennis

Play a fly swatter balloon tennis game where kids try to “swat” falling balloons to show gravity in action.

Gravity Art

Place a large sheet of paper on the floor. Have kids stand up and drip paint onto paper placed on the floor and watch how gravity creates unique patterns. Try using eye droppers or basters! Alternatively, you can take it outside and have kids drop small bouncy balls covered in paint onto the paper. Fun, messy, process art for kids!

Collapsing Towers

Build towers with various materials (e.g., cards, paper cups) and let kids knock them down to see gravity at work. Try this paper cup tower challenge to get started!

Rolling Downhill

Walk outside and have fun rolling balls or toys down a hill to see gravity’s influence. If you are daring roll yourself down the hill.

Playground Fun

Take a trip to the playground and point out how gravity affects you on the slide, monkey bars, and swings! Gravity is always pulling you back down and can make the monkey bars quite challenging!

Slinky Play

A slinky loves gravity and a set of stairs. If your kids have never played with a slinky, it’s a must-try activity.

Remember, preschool-age kids learn best through hands-on play, so try to make these activities engaging and interactive. Encourage their curiosity and ask open-ended questions to help them explore the concept of gravity further. I love the question, “What do you think will happen if_______?”

What is Gravity?

Earth’s gravity is the force that keeps everything on the planet’s surface and makes things fall to the ground. Good thing!

Imagine you are standing on the ground, and there’s an invisible force pulling you down toward the Earth. That force is called gravity. It’s like a giant magnet that attracts everything with mass toward the center of the Earth.

The Earth is super big and has a lot of mass, which means it has a strong pull. That’s why we don’t float away into space like astronauts do when they’re far from Earth. Instead, gravity keeps us firmly planted on the ground.

Have you ever watched a NASA video of an astronaut floating around inside his/her ship?

The Moon also has gravity, but its pull is not as strong because it’s much smaller than Earth. That’s why astronauts can jump higher on the Moon than on Earth!

Even if you can jump really high, you’ll still come back down!

Now, the Earth’s gravity doesn’t just work on you; it also works on everything around you, living and nonliving! It pulls down the trees, the buildings, and even the air you breathe. That’s why things always fall when you drop them. The Earth’s gravity is pulling them like the glass of milk that my son knocked off the table this morning!

When you throw a ball up in the air, it comes back down because of gravity!

Gravity is a fantastic force that keeps our feet on the ground, helps things stay where they are, and makes the world work together. Without gravity, everything would be floating around in space. So, we can thank Earth’s gravity for making our planet such a fantastic place to live!

TIP: Get kids talking about what types of things they think gravity effects in their life!

Books About Gravity

Here are some simple and engaging book ideas that will introduce the concept of gravity in a fun way, making them suitable for preschoolers and kindergarteners who are just beginning to explore scientific concepts.

“Newton and Me” by Lynne Mayer : This beautifully illustrated picture book introduces young children to the concept of gravity through the story of a young boy and his toy. It’s a charming and easy-to-understand book for preschoolers.

“Gravity” by Jason Chin : While this book is suitable for older preschoolers and kindergarteners, it features stunning illustrations and a straightforward explanation of gravity that young children can enjoy with the help of an adult.

“What Is Gravity?” by Lisa Trumbauer : This book from the “Rookie Read-About Science” series is designed for young readers and provides a basic introduction to gravity. It includes simple text and colorful pictures, making it perfect for kindergarteners.

“I Fall Down” by Vicki Cobb : Geared toward preschoolers and kindergarteners, this book playfully explores the concept of gravity. It features interactive experiments and encourages young children to think about gravity daily.

“Gravity Is a Mystery” by Franklyn M. Branley : Part of the “Let’s-Read-and-Find-Out Science” series, this book is aimed at early elementary readers but can be suitable for kindergarteners with adult guidance. It uses simple language and illustrations to explain gravity in a way that young children can grasp.

Helpful Science Resources To Get You Started

Here are a few resources that will help you introduce science more effectively to your kiddos or students and feel confident yourself when presenting materials. You’ll find helpful free printables throughout.

• Best Science Practices (as it relates to the scientific method)
• Science Vocabulary
• 8 Science Books for Kids
• All About Scientists
• Science Supplies List
• Science Tools for Kids

Printable Preschool Activities Pack

Get ready to explore this year with our growing Preschool STEM Bundle .

What’s Included:

There are 12+ fun preschool themes to get you started. This is an ” I can explore” series!

Each unit contains approximately 15 activities, with instructions and templates  as needed. Hands-on activities are provided to keep it fun and exciting. This includes sensory bins, experiments, games, and more! Easy supplies keep it low cost and book suggestions add the learning time. 

This is great! So many fun ways to explore gravity!

AWESOME explanation and such a variety of ways for children to experience gravity! I am in love with your indoor slide combo – wherever did you get it?

I always thought of gravity as too complicated to explain to my preschooler but you nailed it with these fun ways to show gravity in action! The slinky is an awesome idea. My daughter would have a blast falling down and throwing things in the air only to see them fall, all in the name of science! 🙂

What a simple but fun way to explain the meaning of gravity and what it can do. I think reading gravity’s definition in a book makes it more complicated. I am sure Liam did enjoy the whole activity just looking at the photos.

It’s called Rhapsody by Cedar Works. We were lucky to purchase this from a friend used so the cause was significantly lower. S cool to have! Everyone is always jealous when they come over.

Gravity is a fascinating subject. Love a giant slinky experiment – so fun! Thanks for sharing with Afterschool!

Thank you for having us! He had a lot of fun experimenting around the house!

I love these simple experiments! I am featuring it today as part of a round up of Science activities for After School.

Awesome! Thank you. I will stop by to check it out!

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G is for Gravity Experiment

We’re continuing the A to Z Science series  for toddlers and preschoolers here at Inspiration Laboratories with the letter G. G is for Gravity Experiment . Experiment with gravity and have some fun with science.

What is Gravity?

Gravity is a force that attracts things {objects, masses, particles, light}. Most of the time we think about gravity as the reason we are walking on the ground rather than floating in the air. We are attracted to the Earth. Gravity is why objects fall to the ground. The strength of the attraction depends on the mass of the two objects and the distance between them. The greater the mass, the greater the attraction.

How to Explain Gravity to Toddlers and Preschoolers?

For toddlers, you may not even want to explain it to them. It’s okay to just let them experience the concept without actually giving it a name yet. For preschoolers you can simply explain it as this: Gravity is what keeps your feet on the ground. It’s why objects fall to the ground.

Have your child jump up. Ask: Why did you fall back to the ground? Why didn’t you stay in the air?  Because gravity pulled you back down.

Simple Gravity Experiment

Collect a number of balls of different sizes and weights. You might also want to grab a stopwatch. Choose a location to conduct your experiment. You can simply have your child stand on the floor. You could also head to the park and drop balls from atop the playground equipment.

Explain to your child that she is going to drop the balls and see which one hits the ground first. Ask her to predict which ball will hit first. {Choose one over another, or they can both hit at the same time.} It may be easier to drop the balls one at a time. In this case, you’ll want a stopwatch to time the fall.

Have your child hold a ball up and then drop it to the ground.

You can also have your child drop two at a time. Hold the balls at the same height. Be sure to drop them at the exact same time. You might want to practice a few times.

The Results

Did each ball take the same amount of time to hit the ground? They should have. The force of gravity depends on the mass of the object. The greater the mass, the greater the force of gravity. However, no matter the mass, an object will free fall at the same rate {the acceleration due to gravity}. The explanation has to due with inertial mass and a few other things that toddlers and preschoolers will not understand nor should they.

The point of the experiment is to observe gravity at work, ask questions, and make predictions.

If you drop two objects at the same height and they do not hit the ground at the same time, friction and air resistance are most likely to blame. They can slow down an object. Try different shaped objects and see what I mean.

Be sure to check out the rest of the  A to Z Science  series!

Subscribe to the Inspiration Laboratories weekly newsletter. Each issue has exclusive hands-on science explorations for children, a recap of our latest activities, and special resources selected just for you!

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Summer holiday science: turn your home into a lab with these three easy experiments

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Audrey O'Grady receives funding from Science Foundation Ireland. She is affiliated with Department of Biological Sciences, University of Limerick.

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Many people think science is difficult and needs special equipment, but that’s not true.

Science can be explored at home using everyday materials. Everyone, especially children, naturally ask questions about the world around them, and science offers a structured way to find answers.

Misconceptions about the difficulty of science often stem from a lack of exposure to its fun and engaging side. Science can be as simple as observing nature, mixing ingredients or exploring the properties of objects. It’s not just for experts in white coats, but for everyone.

Don’t take my word for it. Below are three experiments that can be done at home with children who are primary school age and older.

Extract DNA from bananas

DNA is all the genetic information inside cells. Every living thing has DNA, including bananas.

Did you know you can extract DNA from banana cells?

What you need: ¼ ripe banana, Ziploc bag, salt, water, washing-up liquid, rubbing alcohol (from a pharmacy), coffee filter paper, stirrer.

What you do:

Place a pinch of salt into about 20ml of water in a cup.

Add the salty water to the Ziploc bag with a quarter of a banana and mash the banana up with the salty water inside the bag, using your hands. Mashing the banana separates out the banana cells. The salty water helps clump the DNA together.

Once the banana is mashed up well, pour the banana and salty water into a coffee filter (you can lay the filter in the cup you used to make the salty water). Filtering removes the big clumps of banana cells.

Once a few ml have filtered out, add a drop of washing-up liquid and swirl gently. Washing-up liquid breaks down the fats in the cell membranes which makes the DNA separate from the other parts of the cell.

Slowly add some rubbing alcohol (about 10ml) to the filtered solution. DNA is insoluble in alcohol, therefore the DNA will clump together away from the alcohol and float, making it easy to see.

DNA will start to precipitate out looking slightly cloudy and stringy. What you’re seeing is thousands of DNA strands – the strands are too small to be seen even with a normal microscope. Scientists use powerful equipment to see individual strands.

Learn how plants ‘drink’ water

What you need: celery stalks (with their leaves), glass or clear cup, water, food dye, camera.

• Fill the glass ¾ full with water and add 10 drops of food dye.
• Place a celery stalk into the glass of coloured water. Take a photograph of the celery.
• For two to three days, photograph the celery at the same time every day. Make sure you take a photograph at the very start of the experiment.

What happens and why?

All plants, such as celery, have vertical tubes that act like a transport system. These narrow tubes draw up water using a phenomenon known as capillarity.

Imagine you have a thin straw and you dip it into a glass of water. Have you ever noticed how the water climbs up the straw a little bit, even though you didn’t suck on it? This is because of capillarity.

In plants, capillarity helps move water from the roots to the leaves. Plants have tiny tubes inside them, like thin straws, called capillaries. The water sticks to the sides of these tubes and climbs up. In your experiment, you will see the food dye in the water make its way to the leaves.

Build a balloon-powered racecar

What you need: tape, scissors, two skewers, cardboard, four bottle caps, one straw, one balloon.

• Cut the cardboard to about 10cm long and 5cm wide. This will form the base of your car.
• Make holes in the centre of four bottle caps. These are your wheels.
• To make the axles insert the wooden skewers through the holes in the cap. You will need to cut the skewers to fit the width of the cardboard base, but leave room for the wheels.
• Secure the wheels to the skewers with tape.
• Attach the axles to the underside of the car base with tape, ensuring the wheels can spin freely.
• Insert a straw into the opening of a balloon and secure it with tape, ensuring there are no air leaks.
• Attach the other end of the straw to the top of the car base, positioning it so the balloon can inflate and deflate towards the back of the car. Secure the straw with tape.
• Inflate the balloon through the straw, pinch the straw to hold the air, place the car on a flat surface, then release the straw.

The inflated balloon stores potential energy when blown up. When the air is released, Newton’s third law of motion kicks into gear: for every action, there is an equal and opposite reaction.

As the air rushes out of the balloon (action), it pushes the car in the opposite direction (reaction). The escaping air propels the car forward, making it move across the surface.

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The moon is too hot and too cold; now it could be just right for humans, thanks to newly available science

Experiments to complete scientific understanding of how reduced gravity affects boiling and condensation

Issam Mudawar’s research on heat transfer could enable space habitats to be built in extreme environments like the moon. (Purdue University photo/John Underwood)

With temperatures on the moon  ranging from minus 410 to a scorching 250 degrees Fahrenheit , it’s an understatement to say that humans will need habitats with heat and air conditioning to survive there long term.

But heating and cooling systems won’t be effective enough to support habitats for lunar exploration or even longer trips to Mars without an understanding of what reduced gravity does to boiling and condensation. Engineers haven’t been able to crack this science – until now.

“Every refrigerator, every air conditioning system we have on Earth involves boiling and condensation. Those same mechanisms are also prevalent in numerous other applications, including steam power plants, nuclear reactors and both chemical and pharmaceutical industries,” said  Issam Mudawar ,  Purdue University ’s Betty Ruth and Milton B. Hollander Family Professor of  Mechanical Engineering . “We have developed over a hundred years’ worth of understanding of how these systems work in Earth’s gravity, but we haven’t known how they work in weightlessness.”

A team of engineers at Purdue led by Mudawar, who is collaborating with NASA’s Glenn Research Center in Cleveland, has spent 11 years developing a facility to investigate these phenomena.

The facility is called the  Flow Boiling and Condensation Experiment (FBCE) . Initial designs  were tested  on  Zero Gravity Corporation ’s (Zero-G) weightless research lab, a specially modified Boeing 727 that flies parabolic maneuvers to create the reduced gravities on the moon and Mars as well as the weightless conditions in space.

Following in-flight testing, NASA Glenn and the agency’s Biological and Physical Sciences Division assisted Mudawar’s team in creating a smaller version of the experiment to fit into the  Fluids Integrated Rack  on the International Space Station. After passing NASA safety and readiness reviews,  FBCE launched to the space station  in August 2021 and has since helped researchers to begin to unlock the mystery of how boiling and condensation work in the extreme environments of space.

These answers are in data the team is collecting from two sets of FBCE experiments taking place on the station. Last July, the facility’s first experiment finished gathering all the data that Mudawar says scientists need to understand how reduced gravity affects boiling. In the coming months, the equipment for the second experiment will launch to the orbiting laboratory as part of a Northrop Grumman commercial resupply services mission for NASA (NG-19) to gather data on how condensation happens in a reduced gravity environment.

Both experiments making up the facility will remain in orbit through 2025, allowing the fluid physics community at large to take advantage of this data.

“We are ready to literally close the book on the whole science of flow and boiling in reduced gravity,” Mudawar said. “Astronauts on the moon will need air conditioning systems, refrigeration systems and many other systems that all require boiling and condensation. Because of the new understanding we’ve received from data showing how these phenomena are influenced by reduced gravity, we are able to provide guidance into how to size the equipment, how to design it effectively and how to predict its performance.”

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Einstein’s big insight that explained Newton’s law of gravity

• Newton’s law of universal gravitation successfully described the motions of objects: from mundane ones here on Earth to the motion of the planets, moons, comets, and more in space.
• But for centuries, there was no explanation or known reason behind why it was an inverse square law: why the strength of the force was proportional to the inverse distance between objects squared.
• Once Einstein came along, however, his picture of curved space not only changed our perception of gravity, but showed how the “inverse square” law was the only possible option. Here’s how.

One of the most revolutionary scientific laws was first put forth by Isaac Newton way back in the 17th century: the law of universal gravitation. Very simply, it hypothesized that between any and all masses in the Universe, there was an attractive force acting on both of them: the force of gravity. But what were the properties of this force? According to Newton, it had to:

• be completely universal, between all objects with mass,
• be proportional to the mass of each object, multiplied together,
• be instantaneous, and traverse the great distances that separated these objects at infinite, unlimited speed,
• and it also needed to get weaker with increased distance, where it fell off in proportion to the square of the distance separating these objects.

This resulted in what physicists call an inverse square force law: where if the distance separating any two objects is given by r , then the force between those two objects is proportional to ~1/ r ².

Newton was able to point out many compelling properties of this inverse square law, including that it led to closed, elliptical orbits, allowed all of Kepler’s laws of planetary motion to be derived from it, and that it led to spheroidal planets where objects always fell “down” toward their centers. But one of the big existential questions remained: why was it an inverse square law? Why was the strength of this force proportional to ~1/ r ², instead of any other possibility? Why was that exponent in the equation “2” rather than any other number?

For hundreds of years, we never knew. Then Einstein came along, and showed it couldn’t be any other way. Here’s why.

When Einstein came along, his big problem with Newtonian gravity was that it didn’t make sense in the context of one of his big breakthroughs from 1905: the notion that there was no such thing as “absolute space” or “absolute time,” but only a unified combination of the two, spacetime. If you were to plant two flags at two different locations, and asked yourself the questions of:

• when were these flags each planted,
• and how far apart these two flags are,

you would think — at least, if you were thinking like Newton — that you could just measure both of them conventionally, with a clock or other timekeeping device to determine when each one was planted and with a measuring device, such as a ruler or a tape measure. It shouldn’t matter, in a Newtonian world, where you were located or how fast you were moving, because those signals would be universal, and the same to all observers.

But, as Einstein so convincingly showed in 1905, this is not so. Physical signals can only travel at a finite speed — limited by the speed of light — and both the “when” of the arrival time of signals that correspond to the moment of the planting of the flag, as well as the “how far apart” distance separating the two flags, are dependent on both where an observer is located as well as how fast (and in what direction) that observer is moving.

We commonly think of these two phenomena as related to one another: length contraction and time dilation. And they are related, precisely because neither space nor time is the thing that’s invariant and absolute, but rather a quantity known as “the spacetime interval” (sometimes called the Einstein interval), which is a combination of an object’s experience as it moves through both space and time together. In Einstein’s universe, the faster you move through space relative to someone who’s stationary, the slower you move through time, and conversely, the slower you move through space, the more rapidly you move through time.

Something that moves at the maximum speed allowable — the speed of light — is especially interesting, because it moves through space at the maximum possible rate. It’s as though time becomes effectively “frozen” for any object that moves at the speed of light, even though, to an outside observer, its speed and motion is still finite: at 299,792,458 m/s. This, too, is something that all observers can agree upon in Einstein’s universe: that the speed of light appears to be constant to everyone. Whether you’re at rest or whether you’re in motion, light always moves at this speed. Your experience of the passage of time or of the separation distance between objects (or even the physical size of objects) might be different dependent on your motion or your location, but the speed of light is not.

This leads us to pose a very interesting question, or “thought-experiment” as Einstein was fond of calling it. We know that the Sun gravitationally attracts the Earth, and that the Earth orbits the Sun due to the Sun’s gravitational influence. We also know that the Earth receives sunlight because the Sun generates that light, and that light then traverses the space between the Sun and Earth.

We also know that the light we see, right now, does not correspond to the light being emitted right now, at this very instant, from the surface of the Sun. Instead, the Sun, from our perspective here on Earth, is located about 150 million km (93 million miles) from the Earth, and so it takes time — about 8 minutes and 20 seconds — for that light to travel through that space, and to journey from the Sun to the Earth, where we can receive and absorb it.

If the Sun were to somehow cease shining, as though it instantaneously went dark, we wouldn’t know about it instantaneously. It would take time — that same 8 minutes and 20 seconds — for the light that was already emitted and that had already begun its journey from the Sun to the Earth (including the light that was already en route ) to finish arriving. Only after the last of that light arrived would the Sun appear to go dark to an observer here on planet Earth.

Well, what if we could somehow imagine the same thing, but instead imagining what would happen to the Sun’s light if it suddenly turned “off” somehow, what would happen to the Sun’s gravitational effects? What would happen if you could somehow imagine “disappearing” the Sun from spacetime itself, and removing that enormous amount of mass — all two nonillion (2 × 10 30 ) kilograms of it — from its present location in space?

How would this removal of the Sun itself affect the Earth, and when would Earth feel those effects?

If we were considering a Newtonian picture of the Universe, the answer would be “instantaneously,” as the very moment the Sun were winked out of existence, the gravitational force between the Sun and Earth — as well as the Sun and every object — would cease to exist. Planets from Mercury out through Neptune would immediately fly off in a straight line, no longer bound by the Sun’s gravity. But Einstein realized this could not be so.

Because there was no way for a signal to traverse these distances instantaneously, and because there was no “action at a distance” in general, the gravitational signal induced by the curved space caused by the Sun’s presence could only propagate at a finite speed — the speed of light — and so it must take that same amount of time, roughly 8 minutes and 20 seconds, for the Earth to cease feeling the gravitational effects of the Sun.

The answer to this question, all on its own, was enough to convince Einstein that the gravitational force between any two separate masses must obey a ~1/ r ² law, as any other answer would be unphysical.

The explanation is straightforward if you think about it. First, think about the Sun: a large, hot, light-emitting sphere of material. As light emanates from the Sun’s photosphere (its outermost layers), it doesn’t just propagate through space; it also spreads out as it departs from the source. The Sun is a sphere, and the light from it propagates spherically outward: in all three dimensions.

As this light spreads out in a sphere, we have to understand that it’s not filling the sphere with light, which would be a three-dimensional volume, but rather that it moves outward in a spherical shell: over a two-dimensional area, like the surface of a globe. As it propagates farther away from the Sun, the light you receive over any given amount of area decreases, as the surface area of a sphere is given by 4π r ². A planet that’s twice as far from the Sun as another receives only one-fourth of the light per unit area; a planet that’s three times as distant receives only one-ninth of the light per unit area.

As a result, the brightness that an object appears to shine at falls off three-dimensionally: as ~1/ r ².

We can imagine a scenario where things didn’t propagate through three-dimensional space, but rather where they propagated through a different number of dimensions. Take, for example, the scenario of dropping a stone into a very still pond of water. Yes, there will be a large initial “splash” in the middle of the pond, where the stone lands, but after the stone strikes the water’s surface, a wave will propagate outward in the shape of a circle, moving across the surface of the water and spreading out not in three dimensions, but only in two.

As a result, if you were to measure the height of the crest of the wave at several points along the water, as you moved away from the impact location of the stone, you’d find that:

• when you’re a certain initial distance away, you measure a certain initial height,
• when you’re twice that initial distance away, the height is one-half of the initial height,
• when you’re three times the initial distance away, the wave’s crest is one-third of the initial height,
• when you’re four times the initial distance away, the wave’s crest is one-fourth of the initial height,

and so on. Because the wave can only propagate along the surface of the water — a two-dimensional surface — it only spreads out proportionally to ~1/ r , since the circumference of a circle is given by C = 2π r .

Einstein’s general relativity is a four-dimensional theory: where one dimension is a time dimension and the other three are spatial dimensions, describing the length, width, and depth (or x , y , and z -directions) we experience. Just as light emitted by the Sun must spread out in three dimensions, but at any instant, that light is confined to the surface of a sphere, so too must the gravitational effects exerted by the Sun: it affects space three-dimensionally, but gets weaker the same way that the surface area of a sphere grows: according to the formula for the area of a sphere’s surface, or 4π r ².

That leads to a force law where gravity gets weaker in precisely the same way: as though it’s proportional to ~1/ r ². The reason gravity follows a ~1/ r ² force law is because we live in a Universe with three spatial dimensions, and as gravity propagates through all three dimensions away from whatever source generated it, it spreads out in all three dimensions. This makes sense, if you think about it.

• Things that propagate in one-dimension, like a compression wave through a slinky, don’t spread out, and so the wave doesn’t weaken, but rather stays constant: proportional to ~1/ r 0 .
• Things that propagate in two-dimensions, like ripples arising from a stone dropped into a pond, spread out like circles, so the height of those ripples fall off proportionally to ~1/ r .
• And things that propagate in three-dimensions, like light or gravity traveling through space, spread out like spheres, so their intensity falls off proportionally to ~1/ r ².

You might then think to ask the question, “What if there are additional spatial dimensions out there beyond the three that we know of?” You might have had the thought that any extra dimensions would provide an extra direction — or degree of freedom — for a physical phenomenon to propagate through. Believe it or not, this thought is correct!

• If the Universe had four spatial dimensions instead of three, both light’s intensity and the strength of the gravitational force would spread out in four dimensions now, and their intensity or strength would fall off proportionally to ~1/ r 3 .
• If the Universe had nine spatial dimensions (as in superstring theory), the gravitational force would fall off proportionally to ~1/ r 8 .
• If, instead, it had ten spatial dimensions (M-theory), it would fall off ~1/ r 9 , while in bosonic string theory, with 25 spatial dimensions, it would fall off proportionally to ~1/ r 24 .

The fact that we can test the behavior of the gravitational force on a wide variety of scales — from cosmic scales to galactic ones down to Solar System scales, all the way down to terrestrial and even microscopic laboratory scales — has confirmed that, everywhere we’ve been able to probe, our Universe only behaves as though there are three spatial dimensions: no more and no fewer.

It remains a possibility that somewhere way down there, perhaps on subatomic scales, there truly are extra spatial dimensions, and thus, extra degrees of freedom in precisely this fashion. If there are extra dimensions, experiments that probe:

• the gravitational force,
• the way that light’s intensity changes,
• or the strength of the electromagnetic force,

should be able to reveal their presence by observing a departure from the conventional, three-dimensional predictions that have proven successful time and time again on all scales.

It was through a series of successful realizations that Einstein, at long last, was able to explain the inverse square (i.e., ~1/ r ²) force law of gravity. If space and time weren’t absolute and gravitation didn’t propagate instantaneously, then gravity had to travel at a finite speed and propagate through space in order to interact with objects in its vicinity. And since signals that travel through space spread out within that space, then the number of dimensions within our Universe would determine how the gravitational force behaved with distance, where a three-dimensional Universe implied exactly a ~1/ r ² force law.

This showed the impossibility of a “fractional exponent” to the gravitational force, as suggested by Einstein’s contemporaries Simon Newcomb and Asaph Hall , and relegated the existence of any “extra” dimensions to tiny, microscopic scales where they would not ruin laboratory or terrestrial experiments that validated the ~1/ r ² nature of gravity. Newton might have been the first to figure out the law of gravity, but it wasn’t until Einstein that we truly understood why it couldn’t be any other way.