Question

A capillary tube of radius $0.4mm$ is dipped vertically in water. Find up to what height the water will rise in capillary. If the capillary is inclined at an angle of of $60$ degree with the vertical, how much length of the capillary is occupied by water? Surface tension of water is $7.0\times 10$ to the power $-2N$ per meter.

Answer 1

For glass water $\theta =0°$

$h=\frac{2T\cos \theta }{r\rho g}=\frac{2\times 7\times {10}^{-2}}{\left(0.4\right)\times {10}^{-3}\times {10}^3\times 9.8}=3.57\times {10}^{-2}m=3.57cm$

$l\cos 60°=h\Rightarrow l=\frac{h}{\cos 60°}=\frac{3.5}{1/2}=7.14cm$