Fluid Mechanics MCQs

Question 1

For one dimensional flow of an incompressible fluid in unsteady state in x-direction, the continuity equation is given by

Accepted Answer

$$\frac{{\partial {	ext{u}}}}{{\partial {	ext{x}}}} = 0$$

Answer

$$\frac{{\partial \left( {ho {	ext{u}}} ight)}}{{\partial {	ext{x}}}} = 0$$

Answer

$$\frac{{\partial {	ext{u}}}}{{\partial {	ext{x}}}} = - \frac{{\partial ho }}{{\partial {	ext{t}}}}$$

Answer

$$\frac{{\partial ho }}{{\partial {	ext{t}}}} = 0$$

Question 2

Velocity head on sudden enlargement in a horizontal pipe is converted into __________ head.

Accepted Answer

Pressure

Answer

Elevation

Answer

Both A and B

Answer

Neither A nor B

Question 3

Diaphragm valves are used for handling __________ fluids.

Accepted Answer

Corrosive

Answer

Viscous

Answer

Non-Newtonion

Answer

Solid suspended

Question 4

Pick out the wrong statement:

Accepted Answer

Friction losses in pipe fittings are generally expressed in terms of velocity heads

Answer

Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer

Answer

Blowers develop a maximum pressure of 2 atmospheres

Answer

Fanning friction factor in case of turbulent flow of liquids in pipe depends upon relative roughness & Reynolds number

Question 5

The velocity for subsonic flow in a pipeline

Accepted Answer

Increases in the downstream direction

Answer

Is constant

Answer

Decreases in the downstream direction

Answer

Is independent of the area of flow

Question 6

What is the value of co-efficient of discharge for square edged circular orifice (for β = 0.3 to 0.5)?

Accepted Answer

0.61 - 0.63

Answer

0.5 - 0.75

Answer

0.75 - 0.90

Answer

0.35 - 0.55

Question 7

The pump used for irrigation purposes is generally designed for

Accepted Answer

Large capacity & low head

Answer

Large capacity & high head

Answer

Small capacity & high head

Answer

Small capacity & low head

Question 8

Out of the following flow measuring devices, which one incurs the maximum installation cost as well as pressure loss?

Accepted Answer

Venturimeter

Answer

Flow nozzle

Answer

Rotameter

Answer

Orificemeter

Question 9

Open channel liquid flow is most conveniently measured by a

Accepted Answer

Notch

Answer

Hot wire anemometer

Answer

Rotameter

Answer

Segmental orifice