Question

a soap bubble was slowly enlarged from radius 4cm to 6cm and amount of work necessary for enlargement is 1.5 *10 calculate the surface tension of soap bubble joules​

Answer 1

The surface tension is 190.2 N/m.

Step-by-step explanation:

Initial radius, r = 4 cm

final radius, r' = 6 cm

Work doen, W = 15 J

Let the surface tension is T.

The work done is given by

W = Surface Tension x change in surface area

`15 = T * 4\pi^2(r'^2 - r^2)\\\\15 = T * 4 * 3.14* 3.14 (0.06^2- 0.04^2)\\\\15 = T* 0.0788\\\\T = 190.2 N/m`