Two soap bubbles `A` and `B` are kept in a closed chamber where the air is maintained at pressure `8 N//m^(2)`. The radii of bubbles `A` and `B` are `2 cm` and `4 cm`, respectively. Surface tension of the soap. Water used to make bubbles is `0.04 N//m`. Find the 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.]A. 2B. 4C. 6D. 8

Two soap bubbles `A` and `B` are kept in a closed chamber where the ai

1.	Two soap bubbles `A` and `B` are kept in a closed chamber where the air is maintained at pressure `8 N//m^(2)`. The radii of bubbles `A` and `B` are `2 cm` and `4 cm`, respectively. Surface tension of the soap. Water used to make bubbles is `0.04 N//m`. Find the 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.]A. 2B. 4C. 6D. 8
Answer» Correct Answer - C The excess of pressure above atmospheric pressure, due to surface tension in a bubble`=(4T)/(r)` The surronding pressure `P_(0)=8 N/m^(2)` `therefore P_(A)` for `1^(st)` bubble `=P_(0)+(4T)/(r_(A))=8+(4xx0.04)/(0.02)` `P_(A)=16N//m^(2)` `P_(B)=P_(0)+(4T)/(r_(A))=12N//m^(2)` `PV=nRT` `(16)(4)/(3)pi(0.02)^(3)=n_(A)RT` `(12)((4)/(3)pi(0.04)^(3))=n_(B)RT` `(n_(B))/(n_(A))=6`

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