Question

Two soap bubbles A and B are kept in a closed chamber where the air is maintained at pressure `8N//m^2`.The radii of bubbles A and B are 2cm and 4cm, respectively. Surface tension of the soap-water used to make bubbles is `0.04N//m`. Find tha ratio `n_B//n_A`, where `n_A` and `n_B` are the number of moles of air in bubbles A and B, respectively. [Neglect the effect of gravity.]

Answer 1

Correct Answer - 6
`P_(A)=P_(0)+P_(A)=P_(0)+(4T)/R_(A)=16N//m^(2)`
`P_(B)=P_(0)+(4T)/R_(B)=12N//m^(2)`
`n_(B)//n_(A)=(P_(B))/(P_(A))((R_(B))/(R_(A)))^(3)=6`