A spherical soap bubble A of radius 2 cm is formed inside another bubble B of radius 4 cm. Show that the radius of a single soap bubble which maintance the same pressure difference as inside the smaller and outside the larger soap bubble is lesser than radius of both soap bubbles A and B.

A spherical soap bubble A of radius 2 cm is formed inside another bubb

1.	A spherical soap bubble A of radius 2 cm is formed inside another bubble B of radius 4 cm. Show that the radius of a single soap bubble which maintance the same pressure difference as inside the smaller and outside the larger soap bubble is lesser than radius of both soap bubbles A and B.
Answer» Solution :From the EXCESS pressure INSIDE a soap bubble `DeltaP = (4T)/R` Here the two bubbles having the same pressure and temperature. So the radius of the combined bubbles. `1/R = 1/(R_1) + 1/(R_2)` `1/R = 1/2 + 1/4 = (2 + 1)/4 = 3/4` `R = 4/3 = 1.33` `:. "" R = 1.33 cm`