Question

The pressure difference across the surface of a spherical water drop of radius 1 mm and surface tension 0.07 N/m is 

(A) 28 Pa 

(B) 35 Pa 

(C) 140 Pa 

(D) 280 Pa.

Answer 1

Correct Option is (C) 140 Pa

R = 1 mm

S = 0.07

\(\Delta P = ?\)

Pressure difference \(\Delta P = \frac{25}{R}\)

\(= \frac{2 \times 0.07}{1 \times 10.3 }\)

\(\Delta P\) = 140 Pa

Answer 2

Correct option is (C) 140 Pa