Question

A child loses his balloon, which rises slowly into the sky.

a) If the balloon is 21.5 cm in diameter when the child loses it, what is its diameter at an altitude of 1150 m? Assume that the balloon is very flexible and so surface tension can be neglected.

b) And what is the diameter of the same balloon at an altitude of 2150 m?

c) And what is the diameter of the same balloon at an altitude of 5150 m?