Fluid Mechanics MCQs

Question 1

An ideal fluid is

Accepted Answer

Both A & B

Answer

Non-viscous

Answer

Incompressible

Answer

Neither A & B

Question 2

An ideal fluid is

Accepted Answer

Frictionless & incompressible

Answer

One, which obeys Newton's law of viscosity

Answer

Highly viscous

Answer

None of these

Question 3

An ideal nozzle design aims at

Accepted Answer

Both A & B

Answer

Minimising wall friction

Answer

Suppressing boundary layer separation

Answer

Neither A nor B

Question 4

Fluid resistance to shear depends upon its

Accepted Answer

Both A and B

Answer

Rate of transfer of molecular momentum

Answer

Cohesion

Answer

Neither A nor B

Question 5

Gradually varied flow in open channel is a/an __________ flow.

Accepted Answer

Steady non-uniform

Answer

Steady uniform

Answer

Unsteady uniform

Answer

Unsteady non-uniform

Question 6

The ratio of the hydraulic radius to the diameter of the channel, for maximum mean velocity of flow in a circular channel, in open channel flow is

Accepted Answer

0.3

Answer

0.9

Answer

0.03

Answer

0.66

Question 7

The frictional resistance in laminar flow does not depend on the

Accepted Answer

Area of surface in contact

Answer

Flow velocity

Answer

Fluid temperature

Answer

Pressure of flow

Question 8

A Newtonion liquid (ρ = density, μ = viscosity) is flowing with velocity v in a tube of diameter 'D'. Let Δp be the pressure drop across the length 'L'. For a laminar flow, Δp is proportional to

Accepted Answer

L ρv2/D

Answer

L μ;V/D2

Answer

D ρv2/L

Answer

Μ V/L

Question 9

Most of the centrifugal pumps used in chemical plants are usually __________ driven.

Accepted Answer

Electric motor

Answer

Steam

Answer

Diesel engine

Answer

Gas turbine