Explain the terms : $($i$)$ Dynamic viscosity, and $($ii$)$ Kinematic viscosity. Give their dimensions.

State the Newton's law of viscosity and give examples of its application.

Enunciate Newton's law of viscosity. Explain the importance of viscosity in fluid motion. What is the

effect of temperature on viscosity of water and that of air?

Define Newtonian and Non$-$Newtonian fluids.

What do you understand by terms : $($i$)$ Isothermal process, $($ii$)$ Adiabatic process, and $($iii$)$ Universal$-$gas

constant.

Define compressibility. Prove that compressibility for a perfect gas undergoing isothermal compression is

$\frac{1}{p}$ while for a perfect gas undergoing isentropic compression is $\frac{1}{wp}.$

Define surface tension. Prove that the relationship between surface tension and pressure inside a droplet of

liquid in excess of outside pressure is given by $p=\frac{4}{d}.$

Explain the phenomenon of capillarity. Obtain an expression for capillary rise of a liquid.

$($a$)$ Distinguish between ideal fluids and real fluids. Explain the importance of compressibility in fluid

flow.

$($b$)$ Define the terms : density, specific volume, specific gravity, vacuum pressure, compressible and

incompressible fluids.

$($R$.$G$.$P$.$ Vishwavidyalaya, Bhopal S $2002)$

Define and explain Newton's law of viscosity.

Convert $1k\frac{g}{s}-m$ dynamic viscosity in poise.

Why does the viscosity of a gas increases with the increase in temperature while that of a liquid decreases

with increase in temperature?

$($a$)$ How does viscosity of a fluid vary with temperature?

$($b$)$ Cite examples where surface tension effects play a prominent role. $($J$.$N$.$T$.$U$.,$ Hyderabad S $2002)$

$($i$)$ Develop the expression for the relation between gauge pressure $P$ inside a droplet of liquid and the

surface tension.

$($ii$)$ Explain the following :

Newtonian and Non$-$Newtonian fluids, vapour pressure, and compressibility.

$($R$.$G$.$P$.$V$.,$ Bhopal S $2001)$

$($B$)$ NUMERICAL PROBLEMS

One litre of crude oil weighs $9\mathrm{.}6$ N $.$ Calculate its specific weight, density and specific gravity.

$[$Ans$.9600\frac{N}{m^3},978\mathrm{.}6k\frac{g}{m^3},0\mathrm{.}978]$

The velocity distribution for flow over a flat plate is given by $u=\frac{3}{2}y-y^{\frac{3}{2}},$ where $u$ is the point

velocity in metre per second at a distance $y$ metre above the plate. Determine the shear stress at $y=9cm.$

Assume dynamic viscosity as $8$ poise. $($Nagpur University$)[$Ans$.0\mathrm{.}839\frac{N}{m^2}]$

A plate $0\mathrm{.}025$ mm distant from a fixed plate, moves at $50c\frac{m}{s}$ and requires a force of $1\mathrm{.}471\frac{N}{m^2}$ to

maintain this speed. Determine the fluid viscosity between the plates in the poise. $[$Ans$.7\mathrm{.}357{10}^{-4}]$

Determine the intensity of shear of an oil having viscosity $=1\mathrm{.}2$ poise and is used for lubrication in the

clearance between a $10$ cm diameter shaft and its journal bearing. The clearance is $1\mathrm{.}0$ mm and shaft

rotates at $200$ r$.$p$.$m$.$

$[$Ans$.[$:$125\mathrm{.}56\frac{N}{m^2}$