We have been learning about John Dunlop and his invention of the pneumatic tyre. He wanted to make wheels bouncy and therefore more comfortable to travel with. We tested 4 different balls for their bounciness : a yellow tennis ball, a wool pom-pom, a solid hockey ball and a green plastic football. We made the comparative test fair by rolling the balls from the same place down a ramp. We measured how far the ball bounced back from a table.
Most us of predicted that the tennis ball would bounce the furthest.
The tennis ball and football bounced back from the table but the football bounced the furthest.
The solid hockey ball hit the table and stopped. It didn’t bounce at all.
The pom-pom didn’t reach to table to bounce at all!
We thought that air inside and the stretchy plastic material of the football made it the bounciest.