the dent in a table tennis ball is removed if it is placed in boiling water. why?

Answer 1

the heat from the boiling water will cause the air in the ball to expand thus pushing the dent and removing it

Answer 2

Hot air is less dense than cold air. So, it takes up more space. You can use this to your advantage with a dented table tennis ball by heating up and expanding the air inside the ball. This pushes the wall of the ball back out.

I don't think the bounce characteristics stay the same though. There will be a weak point in the ball after this happens.

Answer 3

The heat from the boiling water expands the gas inside the ball, forcing the dent to out.

Answer 4

there is air in the ball

if you heat the ball, the air heats up also, and in doing so, expands.

as it expands it exerts a higher pressure on the inside of the ball

if there is a weaker point (in this case, a dent), it will yield as always in the case of the weaker link in a chain. And then when it has yielded the ball is back to normal.

of course this doesn't work with the special heavy balls used to play in very windy conditions, which tend to have a hole or two to start with

Answer 5

Air expands on heating. when the ball is placed in hot water the air inside the ball expands and pushes the dent out.
hope that helps!!

Answer 6

tennis balls are hollow with air. heating the ball expands this air, increasing internal pressure until the force is strong enough to fix the structural fault.

works for ping pong balls too.

Answer 7

Two reasons:
The material is softened and the air inside the ball is expanded.

Answer 8

The air inside of it expands.