MCQ Questions and Answers on Fluid Mechanics

Q.

The vertical component of the force on a curved surface submerged in a static liquid is equal to the

A. Mass of the liquid above the curved surface

B. Weight of the liquid above the curved surface

C. Product of pressure at CG multiplied by the area of the curved surface

D. Product of pressure at CG multiplied by the projected area of the curved surface

Answer : Option:- B

Explanation :

The vertical component of the force on the curved surface is total weight of the liquid contained in the portion extending vertically above the curved surface upto free liquid surface.

Q.

In a flow field, the stream lines and equipotential lines

A. Are parallel

B. Cut at any angle

C. Are orthogonal everywhere in the flow field

D. Cut orthogonally except at the stagnation points

Discuss

Answer : Option:- C

Explanation :

In a flow field, stream lines and equipotential lines are orthogonal to each other.

Q.

Surface tension is due to

A. Viscous forces

B. Cohesion

C. Adhesion

D. The difference between adhesive and cohesive forces

Discuss

Answer : Option:- B

Explanation :

Surface tension is due to cohesion.

Q.

Which law states that when a certain pressure is applied at any point in a fluid at rest the pressure is equally transmitted in all directions and to every other point in the fluid?

A. Newton's law

B. Pascal's law

C. Stokes law

D. Archimedes' principle

Discuss

Answer : Option:- B

Explanation :

Pascal’s law states that when a certain pressure is applied at any point in a fluid at rest the pressure is equally transmitted in all directions and to every other point in the fluid.

Q.

Which property of mercury is the main reason for its use in barometers?

A. High density

B. Negligible capillarity effect

C. Very low vapor pressure

D. Low compressibility

Discuss

Answer : Option:- C

Explanation :

Mercury has low vapour pressure, therefore an excellent fluid to be used in barometers.

Q.

An important law which states that gas solubility is proportional to partial pressure, is known as

A. Newton's law

B. Henry's law

C. Stokes law

D. Hooke's law

Discuss

Answer : Option:- B

Explanation :

Henry’s law is states that solubility of gas is proportional to its partial pressure.

Q.

Which one of the following sets of conditions clearly apply to an ideal fluid?

A. Viscous and compressible

B. Non-viscous and incompressible

C. Non-viscous and compressible

D. Viscous and incompressible

Discuss

Answer : Option:- B

Explanation :

An inviscid (non-viscous) and incompressible fluid is considered as ideal fluid.

Q.

A partially filled tank is carried out on a truck which is moving with a constant acceleration. The water surface in the tank will

A. Move up in the front and move down at the rear

B. Move up at the rear and move down in front

C. Move down in front and also at the rear but move up in the center

D. Remain undisturbed

Discuss

Answer : Option:- B

Explanation :

The water surface in the tank will move up at the rear and move down in the front.

Q.

The height to which a liquid will rise in an open capillary tube is inversely proportional to

A. Temperature of liquid

B. Density of liquid

C. Air pressure

D. Surface tension

Discuss

Answer : Option:- B

Explanation :

Discuss here! No Explaination Available for These Question.

Q.

In flow through a pipe, the transition from laminar to turbulent flow does not depend on

A. Velocity of the fluid

B. Density of the fluid

C. Diameter of the pipe

D. Length of the pipe

Discuss

Answer : Option:- D

Explanation :

The transition from laminar to turbulent flow is decided based on the value of Reynolds number,
Re= ρvD/µ
where,
ρ = density of fluid
v = velocity of fluid
D = diameter of pipe
Thus, It is independent on length of pipe.

MCQ Questions and Answers on Fluid Mechanics

Q. The vertical component of the force on a curved surface submerged in a static liquid is equal to the

Q. In a flow field, the stream lines and equipotential lines

Q. Surface tension is due to

Q. Which law states that when a certain pressure is applied at any point in a fluid at rest the pressure is equally transmitted in all directions and to every other point in the fluid?

Q. Which property of mercury is the main reason for its use in barometers?

Q. An important law which states that gas solubility is proportional to partial pressure, is known as

Q. Which one of the following sets of conditions clearly apply to an ideal fluid?

Q. A partially filled tank is carried out on a truck which is moving with a constant acceleration. The water surface in the tank will

Q. The height to which a liquid will rise in an open capillary tube is inversely proportional to

Q. In flow through a pipe, the transition from laminar to turbulent flow does not depend on

Q.

The vertical component of the force on a curved surface submerged in a static liquid is equal to the

Q.

In a flow field, the stream lines and equipotential lines

Q.

Surface tension is due to

Q.

Which law states that when a certain pressure is applied at any point in a fluid at rest the pressure is equally transmitted in all directions and to every other point in the fluid?

Q.

Which property of mercury is the main reason for its use in barometers?

Q.

An important law which states that gas solubility is proportional to partial pressure, is known as

Q.

Which one of the following sets of conditions clearly apply to an ideal fluid?

Q.

A partially filled tank is carried out on a truck which is moving with a constant acceleration. The water surface in the tank will

Q.

The height to which a liquid will rise in an open capillary tube is inversely proportional to

Q.

In flow through a pipe, the transition from laminar to turbulent flow does not depend on