Question

explain why abicycle tube overfilled with air may brust

Answer 1

This is because as we add more and more air to the tube, the pressure inside increases and the air tries to break open the tube and thus, the tube bursts.

Answer 2

A bicycle tube that is filled with excessive air will burst because more air means more pressure on the tube.  

EXPLANATION:

When a tube is overfilled with air, the pressure inside the tube becomes very high and unequal to the atmospheric pressure. The increased internal pressure is a lot for the tyre tube to bear and so it will burst.

The tube does not have the capacity to take so much pressure and therefore bursts.