Why does a ping-pong ball bounce?

Answer 1

without goin too nerd on you,

It is coz of the air inside the ping pong and the plastic is very light.

making it "weightless"

and it can float because it is less dense than water

Answer 2

Because they are almost weightless and they are hard, which allows them to bounce back up off of other hard surfaces.

Answer 3

Because it doesn't weigh much and it is hard, and you are hitting it against another hard surface, the ping pong table.

Answer 4

Because they are hollow.

Answer 5

For a better bounce on the table.