Cool Physics Experiments to Do at Home

Cool Physics experiments will not only fascinate and amaze your kids but will teach them about important scientific principles.

Some coolest physics experiments include Newton’s cradle, the simple Bernoulli experiment, the balloon rocket experiment, and the density tower experiment. Learn about atmospheric pressure with the egg in the bottle and the rising water experiments.

In this blog post, I will share the details of these and more cool physics experiments that are perfect for young kids and teenagers. These experiments are not only educational but also fun. I hope you enjoy them.

Photo: Unsplash

7 Cool Physics Experiments to Do at Home

Here are the 7 most fun Physics experiments you can do at home.

1. Newton’s Cradle Experiment

Newton’s cradle experiment demonstrates the conservation of momentum and energy.

How to do it

You will need the following items:

  • A set of Newton’s Cradle balls (or any type of metal balls that are identical in size and weight)
  • A table or other flat surface
  • Strings that are the same length

Attach one end of each string to a different ball. Suspend the balls from a frame so that they are touching each other. You can easily achieve this by making sure the strings are the same length and attaching them to a board at the same height.

Pull back one ball and release it so that it hits the middle ball. The released ball will swing up and hit the ball at the opposite end. That ball will then swing up and hit the ball next to it and so on. The last ball will swing up and hit the first ball, starting the process all over again.

Newtons Cradle (Photo: Unsplash)
Newtons Cradle (Photo: Unsplash)

The results explained

What is happening is that the balls are colliding in such a way that the momentum of each ball is conserved. In other words, the combined momentum of all the balls before the collision is equal to the combined momentum of all the balls after the collision.

The energy is also conserved in this experiment. The energy is converted from kinetic energy (the energy of motion) to potential energy (the energy stored in the balls as they are raised up) and back to kinetic energy again.

This is a simple but elegant demonstration of some very important scientific principles. Try it yourself and see.

2. The Simple Bernoulli Experiment

The Bernoulli principle is one of the most important principles of fluid dynamics. It explains how wings generate lift and how airfoils work. When the speed of a fluid increases, the pressure decreases. This principle is what makes flight possible.

Here’s how to do it

You will need the following items:

  • A piece of paper
  • A straw
  • A pair of scissors
  • Tape

Cut a rectangular piece of paper that is about twice as wide as the straw. Fold the paper in half lengthwise and tape it together.

Cut a slit in the center of the paper, being careful not to cut all the way through. Insert the straw into the slit and tape it in place. Now blow gently across the top of the paper. What happens?

The results explained

When you blow across the top of the paper, the airspeed above the paper increases. An increase in airspeed means a decrease in pressure. The decrease in pressure on the top of the paper is greater than the increase in pressure on the bottom of the paper. This creates a force that lifts the paper up into the air.

This is how airplanes generate lift. The wings are shaped so that the air travels faster over the top of the wing than the bottom. This decreases the pressure on the top of the wing and creates lift.

Try this experiment with different shapes of paper and see how it affects the results.

3. The Egg in the Bottle Experiment

This experiment demonstrates how atmospheric pressure and temperature can affect the shape of an object.

How to do it

You will need the following items:

  • A hard-boiled egg
  • A glass bottle with a narrow neck
  • A piece of paper
  • A lighter

Remove the shell from the hard-boiled egg. Place it in the mouth of the glass bottle. The mouth should be just smaller than the egg in diameter so the egg doesn’t fall through.

Roll the piece of paper into a cone shape and hold it over the neck of the bottle. Light the paper on fire, remove the egg and drop the burning paper into the bottle. Quickly place the egg back in the mouth of the bottle. What happens?

The results explained

The fire goes out almost immediately because the oxygen in the bottle is quickly used up. After some time, the egg drops into the bottle.

Before we placed the burning paper into the bottle, the atmospheric pressure inside the bottle was the same as the atmospheric pressure outside. So there was no pressure pushing the egg into the bottle.

When we placed the burning paper in the bottle, it heated up the air inside the bottle. The air inside the bottle expanded. When we sealed the bottle with the egg, the fire went out and the air inside the bottle contracted. This created a vacuum.

The atmospheric pressure outside the bottle became greater than the atmospheric pressure inside the bottle, so the egg was forced into the bottle.

4. The Balloon Rocket Experiment

The Balloon Rocket is a classic physics experiment that demonstrates Newton’s Third Law of Motion: for every action, there is an equal and opposite reaction. In simple terms, it is all about thrust.

Here’s how to do it

You will need the following items:

  • A balloon
  • A straw
  • Tape
  • Scissors
  • String
  • Two chairs or a table
  • A plastic clip or peg

Place two chairs a few feet apart or use a table. Cut a length of string and tie one end to the back of one chair. Thread the other end through the straw and tie it to the back of the other chair. The string should be taut but not too tight.

Cut two small pieces of tape and affix them on the top part of the straw, about an inch apart. These will be used to hold the balloon in place.

Blow up the balloon, twist the neck, and use the peg to make sure the air doesn’t escape. Now attach the balloon to the straw using the two pieces of tape.

Remove the peg and release the balloon and watch it fly!

The results explained

Once you remove the peg and release the balloon, the air will rush out of the balloon in one direction with great force. The straw will be forced in the opposite direction with an equal force. This is because of Newton’s Third Law of Motion. The faster the air rushes out of the balloon, the greater the force will be.

5. The Candle in the Jar Experiment

This experiment is a great way to learn about the relationship between air and combustion.

How to do it

You will need the following items:

  • A candle
  • A glass jar
  • A wooden board or a ceramic plate
  • A lighter or matches

Light the candle and place it on a wooden board or ceramic plate. Quickly put the glass jar upside down on top of the candle. After some time, the flame will go out.

The results explained

The flame will keep burning for some time before it eventually goes out. Combustion requires oxygen. When you put the jar on top of the candle, you create a sealed environment. The oxygen inside the jar is quickly used up and the flame goes out.

If you want to see the flame burning for longer, try using a bigger jar. The bigger jar will trap more oxygen than the smaller jar and the flame will burn for a longer period of time.

6. Density Tower Experiment

This is another fun Physics experiment that you can do at home. It’s a great way to learn about density and how some liquids are heavier or denser than others.

How to do it

You will need the following items:

  • A clear plastic bottle with a screw-on lid
  • Water
  • Vegetable oil
  • Honey
  • Food coloring
  • Turkey baster
  • Marker
  • You may also need other liquids such as rubbing alcohol, milk, dish soap, etc.

Mix some drops of food coloring into your water and mix well. Add equal parts of all the liquids into the bottle. Start with one liquid before going to the next. Each time you add a liquid, make sure it doesn’t touch the sides of the bottle.

You can start by ranking all the liquids based on how dense you think they are and then add them starting with the densest. After adding all the liquids, close the bottle and let it sit for some time.

The results explained

The liquids will form layers based on their density. The densest liquid will be at the bottom and the lightest liquid will be at the top. This experiment tells us that some liquids are heavier than others.

The lighter liquid will float on top of the denser liquid because it is less dense.

7. Rising Water Experiment

The rising water experiment is a great way to learn about air pressure, heat, expansion, and contraction.

Here’s how to do it

You will need the following items:

  • A votive candle
  • A clear glass jar
  • A shallow dish
  • Water
  • Lighter or Matches
  • Food coloring (Optional)

Pour some water into a shallow dish. You will only need just enough to cover the bottom part of the dish. You can add food coloring to the water for better visibility. Place the votive candle in the center of the jar and light it using a lighter or matches.

Immediately you light the candle, place the clear glass jar upside down on top of the shallow dish. Observe what happens to the water inside the jar.

The results explained

When you light the candle, the heat from the flame will start to heat up the air inside the jar. The air inside the jar expands, but soon, the oxygen inside is depleted and the candle goes out.

The heated air inside the jar starts to cool and contracts. As the air inside the jar cools, it creates a vacuum. The atmospheric pressure outside is greater than the pressure inside the jar and this causes water to be forced up the jar.

Why Physics Experiments Are Great for Kids

Here’s why you might want to start helping your kids perform fun Physics experiments at home:

They Foster Curiosity

Kids are fascinated by the world around them, and there is no better way to foster that curiosity than through hands-on learning. Physics experiments are a great way to introduce your kids to the basic concepts of science while also providing them with some fun and engaging activities.

Physics Experiments Encourage Observation and Exploration

You will appreciate the value of good observation skills when your kids are constantly asking you how things work. Physics experiments provide a perfect opportunity for kids to practice their observational skills while also exploring the world around them.

They Help Kids Develop Problem-Solving Skills

Nothing is more satisfying than watching your child figure out how to solve a problem on their own. Physics experiments can help kids develop their problem-solving skills as they learn how to apply the concepts they are observing.

Physics Experiments Are a Great Opportunity for Family Bonding

There is no better way to spend some quality time with your kids than by helping them with their physics experiments. Not only will you get to bond with your kids, but you will also get to share in their excitement as they learn about the world around them.

Evaluation and Critical Thinking

Another great benefit of physics experiments is that they help kids develop their evaluation and critical thinking skills. As your kids experiment, they will learn how to identify the variables that are affecting their results. This will help them develop their ability to think critically about the world around them.

So, what are you waiting for? Get started on some cool physics experiments with your kids today. The ones listed here are among the most fun that you can do at home. Not only are they fun, but they’re also a great way to learn about the world around us.

Do you have any other cool Physics experiments that you like to do at home? Share them with us in the comments below.


Recent Posts