Question

A capillary tube of radius $0.5$ mm is immersed in a beaker of mercury. The level inside the tube is $0.8$ cm below the resonance and angle of contact is $120^\circ$. What is the surface tension of mercury if the mass density of mercury is $\rho = 13.6 \times 10^3$ kgm$^{-3}$ and acceleration due to gravity is $g = 10$ m/s$^2$?}

• A. $0.225$ N/m
• B. $0.544$ N/m
• C. $0.285$ N/m
• D. $0.375$ N/m
• E. $0.425$ N/m

Hint:

For mercury, $\cos\theta$ is negative $\Rightarrow$ depression occurs.

Answer 1

The Correct Option is D