Embibe Experts Solutions for Chapter: Viscosity and Surface Tension, Exercise 2: Exercise-2

A ball of mass $m$ and radius $r$ is released in a viscous liquid. The value of its terminal velocity is proportional to :

In Poiseuilli's method of determination of coefficient of viscosity, the physical quantity that requires greater accuracy in measurement is

What is the velocity $v$ of a metallic ball of radius $r$ falling in a tank of liquid at the instant when its acceleration is one-half that of a freely falling body ? (The densities of metal and of liquid are $\rho$ and $\sigma$ respectively, and the viscosity of the liquid is $\eta$).

According to Newton, viscous force is given by

$F=-\eta A\frac{dv}{dx}$

where $\eta =$ coefficient of viscosity, so dimensions of $\eta$ will be :

The diagram shows a cup of tea seen from above. The tea has been stirred and is now rotating without turbulence. A graph showing the speed $v$ with which the liquid is crossing points at a distance $\mathrm{X}$ from $\mathrm{O}$ along a radius $\mathrm{XO}$ would look like

A soap bubble in vacuum has a radius of $3 \mathrm{cm}$ and another soap bubble in vacuum has a radius of $4 \mathrm{cm}$.
If the two bubbles coalesce under isothermal condition, then the radius of the new bubble is

In a vessel equal masses of alcohol (sp. gravity $0.8$) and water are mixed together. A capillary tube of radius $1 \mathrm{mm}$ is dipped vertically in it. If the mixture rises to a height $5 \mathrm{cm}$ in the capillary tube, the surface tension of the mixture is

A spherical soap bubble of radius $1.0 \mathrm{cm}$ is formed inside another of radius $2 \mathrm{cm}$. If a single soap bubble is formed which maintains the same pressure difference as inside the smaller and outside the larger bubble, the radius of this bubble is