Question

The amount of energy required to form a soap bubble of radius 2 cm from a soap solution is nearly: (surface tension of soap solution = 0.03 N m^-1)

(1) 5.06 x 10^-4 J

(2) 3.01 x 10^-4 J

(3) 50.1 x 10^-4 J

(4) 30.16 x 10^-4 J

Answer 1

Correct option is (2) 3.01 x 10^-4 J

E = 2T(4πR²)

= 2(0.03) (4) (3.14) (2 x 10^-2)²

= 3.01 x 10^-4 J