Fluid Mechanics MCQs

Question 1

The rate of change of moment of momentum represents the __________ by the fluid.

Accepted Answer

Torque applied

Answer

Force exerted

Answer

Work done

Answer

Power developed

Question 2

Venturimeter and orificemeter measures the __________ of the fluid.

Accepted Answer

Average velocity

Answer

Pressure

Answer

Maximum velocity

Answer

Point velocity

Question 3

Each term in Bernaulli's equation represents the __________ of the fluid.

Accepted Answer

Energy per unit weight

Answer

Energy per unit mass

Answer

Force per unit mass

Answer

None of these

Question 4

Drag force on the float of a rotameter is (where, Q = flow rate of the fluid)

Accepted Answer

Constant

Answer

$$ \propto {	ext{Q}}$$

Answer

$$ \propto \sqrt {	ext{Q}} $$

Answer

$$ \propto {{	ext{Q}}^2}$$

Question 5

Which of the following facilitates close control of flow of fluids?

Accepted Answer

Globe valve

Answer

Gate valve

Answer

Butterfly valve

Answer

Check valve

Question 6

In area meter (e.g., rotameter), with increase in the fluid flow rate, the

Accepted Answer

Pressure drop is almost constant

Answer

Pressure drop increases linearly

Answer

Area through which fluid flows does not vary

Answer

None of these

Question 7

Hydraulic radius of 6" × 12" cross-section, is __________ inches.

Accepted Answer

2

Answer

0.5

Answer

1.5

Answer

None of these

Question 8

In case of a __________ the energy of flow is considerably decreased downstream of the machine.

Accepted Answer

Turbine

Answer

Blower

Answer

Centrifugal pump

Answer

Centrifugal fan

Question 9

Select the correct statement.

Accepted Answer

The discharge through a venturimeter depends upon Δp only and is independent of orientation of the meter

Answer

A venturimeter with a given gage difference discharges at a greater rate, when the flow is vertically downward through it, than when the flow is vertically upward

Answer

For a given pressure difference, the discharge of gas is greater through a venturimeter, when compressibility is taken into account, than when it is neglected

Answer

The overall pressure loss is the same in a given pipe line, whether a venturimeter or a nozzle with the same throat dia is used