Embibe Experts Solutions for Chapter: Viscosity and Surface Tension, Exercise 5: Exercise (Previous Year Questions)

The wettability of a surface by a liquid depends primarily on:

Water rises to a height $h$ in capillary tube. If the length of capillary tube above the surface of water is made less than $h$ then :

Two objects $A \text{and} B$ of equal density and radii $r_{\mathrm{A}}=1 \mathrm{mm}$ and $r_{\mathrm{B}}=2 \mathrm{mm}$ are moving in the same medium. Then, find the ratio of their terminal velocity $\frac{V_{\mathrm{B}}}{V_{\mathrm{A}}}$ in the medium.

A rectangular film of liquid is extended from $\left(4 \mathrm{cm}\times 2 \mathrm{cm}\right) \text{to} \left(5 \mathrm{cm}\times 4 \mathrm{cm}\right)$. If the work done is $3\times {10}^{-4} \mathrm{J}$, the value of the surface tension of the liquid is,

Three liquids of densities ${\rho }_1, {\rho }_2$ and ${\rho }_3$ (with $\left.{\rho }_1>{\rho }_2>{\rho }_3\right),$ having the same value of surface tension T, rise to the same height in three identical capillaries. The angles of contact ${\theta }_1$ ${\theta }_2$ and ${\theta }_3$ obey 

Two arteries are of same length and the ratio of their radii is $1:3$. The pressure difference across ends of both arteries are same. Find out the ratio of the rate of flow.

If a capillary is dipped into water, then up to what height will water rise? Given, $T=0.072 \mathrm{N} {\mathrm{m}}^{-1}\text{,} r=5 \mathrm{mm}\text{,} g=10 \mathrm{m} {\mathrm{s}}^{-2}$.

Water is filled in a cylindrical tube having diameter $1 \mathrm{mm}$ and length $50 \mathrm{cm}$. If surface tension of water is $0.055 \mathrm{N} {\mathrm{m}}^{-1}$, then find pressure difference across meniscus of water in container.