Question

How much amount of work is done in forming a soap bubble of radius r?q2

Answer 1

Let T be the surface tension of a soap solution.

The initial surface area of soap bubble = 0

The final surface area of soap bubble = 2 × 4πr²

∴ The increase in surface area = 2 × 4πr²

The work done in blowing the soap bubble is

W = surface tension x increase in surface area

=T × 2 × 4πr² = 8πr²T