Why do objects thrown in the air always come back down?
Hypotheses: Ask children why everything we throw up into the air falls back down to the ground. Have them predict what will reach the ground first if we let a sheet of paper and a book fall to the ground at the same time. If we crumple up the piece of paper, will the result be the same? Ask them why all objects fall to the ground instead of floating in the air.
- A chair
- A book which can be held in one hand by a child
- 2 sheets of paper the same size as the book or a little smaller
- Other objects of different weight (pebble, ball, pencil, etc.)
- The daycare worker chooses a child to stand on the chair.
- The other children sit on the floor, not too close to the chair.
- The child on the chair holds the first two objects (book and smooth sheet of paper) in front of him horizontally and at the same level.
- When the daycare worker gives the signal, the child lets go of both objects at the same time.
- Watch how the sheet of paper gently dances in the air as it goes down. As children probably predicted, the book hits the ground first.
- Another child stands on the chair and repeats the experiment with the same book. This time however, he holds a crumpled piece of paper in the other hand. Is the result different?
- Finally, another child climbs onto the chair. He places the smooth sheet of paper on the book and drops them. What happens?
- Try a variety of different objects.
Explanations: At first, you probably thought the book would touch the ground first since it is heavier.
However, once the piece of paper was crumpled, they hit the ground at the same time! Funny, since it is the same piece of paper and the book is still heavier. It all comes down to form.
When the paper is smooth, it exposes a large surface to the air beneath it which slows its descent. Once it is crumpled, the surface which comes in contact with the air is much smaller, allowing it to fall much faster.
When the sheet of paper is placed on the book, there is no air at all beneath it. For this reason, the two objects fall at the same speed. This force is called gravity. It attracts objects to the ground like a magnet.
All objects are attracted to the ground by the same force, gravity. They all fall at the same speed unless air offers a resistance strong enough to slow them down.
a Bachelor's Degree in Biological Science. She has worked in a
laboratory and tested her knowledge. She has taught Math, Chemistry, and
Physics. She has also developed a simplistic and innovative approach
designed to introduce young children to scientific experiments, old and
new. She created her friend Globule. This character is sometimes red,
and sometimes white. He guides little ones through their scientific
experiments and discoveries. It is clear to see Angélique is passionate
about children and science. Globule's Approach.