Drop Race
Word of the day: gravity
“If I drop a big heavy book and a tiny little ball at the same time, which one wins?”
Grab
- a hardcover book
- a small ball
- a sheet of paper
- a soft landing spot (rug or pillow)
Do
- Ask for a guess first. Then hold the book and the ball at the same height and let go together. Listen for one thump or two.
- Race the book against a flat sheet of paper. The paper loses.
- Crumple the paper into a tight ball and race again.
- Last trick: lay the flat paper ON TOP of the book and drop them together.
The big moment
Paper on top of the book. It should lose, and it ties.
Ask (guess first, then try)
- Heavy or light, who wins?
- Why did the flat paper float down slowly?
- What happened when the paper rode on the book?
What's going on (for you)
Gravity pulls everything down at the same rate. Heavy things only seem to win when air gets in the way: flat paper catches lots of air, crumpled paper doesn't. Riding on the book, the paper is shielded from the air and falls just as fast.
If they want more
Try a feather or a tissue. Galileo is supposed to have done this off a tower; an astronaut did it on the Moon with a hammer and a feather, and they landed together because there's no air.