A soap bubble has radius 2 mm and surface tension 0.05 N/m. If its excess internal pressure is N Pa, find N.

Question

G1 Physics · Accepted Answer

A soap bubble has two surfaces. Therefore, ΔP = 4S/R. Substitute S = 0.05 N/m, R = 2×10⁻³ m. Thus, ΔP = 4×0.05/ [2×10⁻³] = 100 Pa. Hence, N = 100.