Two soap bubbles of radius `R_(1) and R_(2) (lt R_(1))` are joined by a straw. Air flows from one bubble to another and a single bubble of radius `R_(3)` remains.

(a) From which bubble does the air flow out ?
(b) Assuming no temperature change and atmospheric pressure to be `P_(o), find the surface tension of the soap solution.

Answer

(a) From smaller bubble (b) `T=(P_(o)(R_(3)^(3)-R_(1)^(3)-R_(2)^(3))/(4(R_(1)^(2)+R_(2)^(2)-R_(3)^(2))`