Question

derive the expression for excess pressure inside a soap bubble​

Answer 1

Answer:

Derive an expression for excess of pressure inside a soap bubble. Consider a soap bubble of radius R and surface tension T. ... Due to excess pressure inside the liquid drop, the free surface of the drop will experience the net force in the outward direction due to which the drop will expand.

Answer 2

Answer:

ANSWER

The net upward force on the top hemisphere of the liquid is just the pressure difference times the area of the equatorial circle :

F upward =(P1′−P0)πr2 where Fupward= upward force on the liquid due to air-currents;

P1′= Final pressure; P0= Initial pressure; r= radius of the drop, assuming it to be spherical.

The surface tension force downward around circle is equal to the surface tension of the circumference, since only one surface contributed to the force :

Thus, Fdownward=T(2πr) where, T= surface tension.

This gives, P1−P0=r2T which represents the excess pressure inside the liquid drop.