This is a cool science project. looks cool I guess, have not tried it yet.
You will want to get a large rubber type of kick ball and a tennis ball.

If you looking at the two balls they both have the potential to have energy. At the moment while you are holding them they do not have any energy or are utilizing any.

If you drop them at the same time onto a concrete floor or surface and then catch them you will probably notice that they almost bounced at the same height. However, if you think about the amount of energy needed to pick each one up you would think that the larger ball would need more energy to move so you would feel the larger ball is producing more energy. The force of gravity on the larger ball is actually more because of its size allowing more force to be placed against it. As it hits the ground it compresses and has a larger area to compress. When this happens, the energy accumulated from the fall transfers upward and since there was more area there is more energy pushed upward thereby forcing the bigger ball to have more force and propel higher.

How can we transfer the energy from the big ball to the smaller ball to get it to go higher?

We need to put the small ball on top of the larger ball.

Make a little cup type of holder with duct tape and put it onto the large ball. It should be about 1 inch tall so the tennis ball can fit inside of it. Place the small one in the tape style cup holder on top of the large one and then hold the big ball and drop it to the ground.

You should see the small ball rocketed to a great new height and the larger one lose a little of its energy compared to the first bounce.

What happened here? The large ball compressed as it contacted the concrete floor and then propelled its energy upward. Since there is more energy because of the size of this ball and area the energy was pushed upward and into the small ball which gave this small ball so much energy that it was able to travel to a new height.

This is a great demonstration science project for the fair.
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