Why doesn't it bounce as high as I dropped it?

A falling ball is full of moving energy. When it squashes, some of that energy turns into a little warmth inside the ball. Only the rest goes into the push back up. So each bounce is a bit lower than the one before.

Why doesn't every ball bounce?

Rubber is springy. It squashes, then pops back into shape. Putty isn't springy. Drop a ball of putty and it squashes flat and stays that way. Its moving energy turns into warmth instead of a push, so it just goes splat.

Why does a ball bounce?

Roo answers for ages 4–11, then goes 2 steps deeper each time a child asks why.

Roo says

Drop a rubber ball and watch closely. When it hits the ground, its bottom squashes flat for a moment. Then the rubber springs back into its round shape, pushing against the ground, and the ground pushes the ball back up. Boing!

For ages 4–7

Checked against Why do balls bounce? (Exploratorium)
Why doesn't it bounce as high as I dropped it?

A falling ball is full of moving energy. When it squashes, some of that energy turns into a little warmth inside the ball. Only the rest goes into the push back up. So each bounce is a bit lower than the one before.

For ages 6–9

Checked against Why do balls bounce? (Exploratorium)
Why doesn't every ball bounce?

Rubber is springy. It squashes, then pops back into shape. Putty isn't springy. Drop a ball of putty and it squashes flat and stays that way. Its moving energy turns into warmth instead of a push, so it just goes splat.

For ages 8–11

Checked against Why do balls bounce? (Exploratorium)