Question

41. A capillary tube of radius 1 mm is dipped in water of surface tension 0.073 N m. Find the weight of water that rises in the tube. Take angle of contact 0 = 0° ​

Answer 1

Given:-

Radius of capillary tube = 1mm

surface tension = 0.073 N m

Angle of contact = 0°

To find:-

Weight of water rise in tube

Solution:-

We know that,

The rise of a column of liquid within a narrow capillary tube is also because of the surface tension.

The formula for capillary rise is denoted by 'h'

The rise in level of water is given by;

h = 2× ( 0.073)×cos0°/[10^(-3)]×[10^3]×[10]

Now,

weight of water rised in the capillary tube is given by;

=> w = mg

=> (10^3)×22/7×[10^(-3)]^2×{2× ( 0.073)×cos0°/ [10^(-3)]×[10^3]×[10]}×10

=> w = 4.586×10^(-4) kg

Hence the weight of water rised in the capillary tube is 4.586×10^(-4)kg.