Fluid Mechanics MCQs

Question 1

The pressure and power requirement of a gas fan at constant speed & capacity varies __________ the gas density.

Accepted Answer

Directly as

Answer

Inversely as square root of

Answer

Inversely as

Answer

As square of

Question 2

For a fluid rotating at constant angular velocity about vertical axis as a rigid body, the pressure intensity varies as the

Accepted Answer

Square of the radial distance

Answer

Radial distance linearly

Answer

Inverse of the radial distance

Answer

Elevation along vertical direction

Question 3

To handle smaller quantity of fluid at higher discharge pressure, use a __________ pump.

Accepted Answer

Reciprocating

Answer

Centrifugal

Answer

Volute

Answer

Rotary vacuum

Question 4

What is the ratio of fluid carrying capacity of two pipes having diameters d1 and d2 respectively?

Accepted Answer

$${\left( {\frac{{{{	ext{d}}_1}}}{{{{	ext{d}}_2}}}} ight)^{0.5}}$$

Answer

$${\left( {\frac{{{{	ext{d}}_1}}}{{{{	ext{d}}_2}}}} ight)^{0.8}}$$

Answer

$$\frac{{{{	ext{d}}_1}}}{{{{	ext{d}}_2}}}$$

Answer

$${\left( {\frac{{{{	ext{d}}_1}}}{{{{	ext{d}}_2}}}} ight)^2}$$

Question 5

What is the pipe called which lifts water from a reservoir to a greater height than the initial level in the supply reservoir?

Accepted Answer

Siphon

Answer

Penstock

Answer

Tunnel

Answer

Pressure pipeline

Question 6

Quicksand is an example of a __________ fluid.

Accepted Answer

Dilatent

Answer

Bingham plastic

Answer

Newtonion

Answer

Pseudoplastic

Question 7

Drag is the force component exerted on an immersed object,

Accepted Answer

The component being parallel to theflow direction

Answer

Passing the centroid of the body at 60°to the direction of motion

Answer

The component being normal to the flow direction

Answer

None of these

Question 8

In case of a pipe exit fitted with a nozzle, the

Accepted Answer

Both B and C

Answer

Conversion of kinetic head to pressure head is facilitated

Answer

Conversion of pressure head to kinetic head is facilitated

Answer

Power transmitted through the nozzle is maximum, when the head lost due to friction in the pipe is equal to one third of the total supply head

Question 9

Reynolds number is the ratio of

Accepted Answer

Inertial forces to viscous forces

Answer

Viscous forces to gravity forces

Answer

Viscous forces to inertial forces

Answer

Inertial forces to gravity forces