Answer to Question #232847 in Classical Mechanics for ava

Question

Radius of capillary is 2mm. A liquid of weight 6.28 x 10^-4N may remain in the capillary, then the surface tension of liquid will be?

Answer 1

$γ = \frac{F}{l}$

$\text{The surface tension forces F are numerically equal to the weight }$

$\text{of the liquid in the capillary.Since the liquid in the capillary}$

$\text{is in equilibrium.}$

$F = 6.28*10^{-4}N$

$l =2\pi r$

$r = 2mm = 2*10^{-3}m$

$γ = \frac{F}{l}= \frac{6.28*10^{-4}}{2*\pi*2*10^{-3}}\approx0.05\frac{N}{m}$

$\text{Answer: }0.05\frac{N}{m}$