Question

The ratio of the surface tension S and density ρ of liquid 1 and 2 are 1:2 and 1:4 respectively. Equal amount of the two liquids is poured into two identical tubes. what will be the ratio of the rise in the liquid level in the two tubes? (Assume the angle of contact to be same)

(a) 1:2

(b) 2:1

(c) 8:1

(d) 1:8

This question was addressed to me by my school teacher while I was bunking the class.

The question is from Surface Tension topic in portion Properties of Fluids of Fluid Mechanics

Answer 1

Right answer is (b) 2:1

The best explanation: where h = rise in liquid height in the tube, S = surface tension, θ = the angle of contact, d = diameter of the tube, ρ = density of liquid and g = acceleration due to gravity.

Given, S1 / ρ1 = 1 : 2 and S2 / ρ2 = 1 : 4.