Question

Find the gauge pressure in pascals in a soap bubble 0.04 m in diameter. The surface tension is 25.0 x 10^4 Pa.

Answer 1

hint:
Assume the soap bubble is free-floating in the air:
Pi-Po=4T/r

Answer 2

4r/g
4x30.0x10/2x10
1200/20
60N/M