Two soap bubbles have radii 2 cm and 6 cm and are in contact. If the common separating soap film has radius of curvature N cm, find N.

Question

G1 Physics · Accepted Answer

For two contacting soap bubbles, 1/R(c) = 1/R₁−1/R₂, where R₂ is the larger radius. Therefore, R(c) = R₁R₂/(R₂−R₁). Substitute R₁ = 2 cm, R₂ = 6 cm. Hence, R(c) = 2×6/(6−2) = 12/4 = 3 cm. Therefore, N = 3.