# MCQ on Fluid Mechanics

MCQ on Fluid Mechanics

1-Rain drops are spherical because of:

(A) viscosity

(B) air resistance

(C) surface tension

(D) atmospheric pressure

2-An ideal fluid is one which

(A) Obeys Newton’s law of viscosity

(B) Flows through pipes with least friction

(C) is frictionless and incompressible

(D) satisfies continuity equation

3-Bernolli’s equation deals with the principal of conservation of:

(A) Momentum

(B) Energy

(C) Mass

(D) Force

4-Standard atmospheric pressure in terms of water column is:

(A) 9.81 m

(B) 8.75 m

(C) 12.35 m

(D) 10.33 m

5-The essential feature of turbulent flow:

(A) Large discharge

(B) High discharge

(C) Velocity at a point remains constant with time

(D) Velocity and pressure at a point exhibits irregular fluctuations of high frequency

6-The laminar flow is characterized by:

(A) Irregular motion of fluid particle

(B) Fluid particle moving in layers parallel to the boundary surface

(C) Existence of eddies

(D) High Reynold’s number of flow

7-Venturi meter is a device used for measuring

(A) Flow rate

(B) Piezo metric head

(C) Velocity head

(D) Pressure

8-Gauge pressure at a point is equal to:

(A) Absolute pressure minus atmospheric pressure

(B) Absolute pressure plus atmospheric pressure

(C) Vacuum pressure plus absolute pressure

(D) Vacuum pressure minus atmospheric pressure

9-The discharge through a rectangular notch is given by

(A) Q = 2/3[CdL(2g)1/2H5/2]

(B) Q = 8/15[CdL(2g)1/2H3/2]

(C) Q = 8/15[CdL(2g)1/2H5/2]

(D) Q = 2/3[CdL(2g)1/2H3/2]

10-The co-efficient of discharge Cd in terms of Cv and Cc:

(A) Cd = Cv/Cc

(B) Cd = Cv x Cc

(C) Cd = Cc/Cv

(D) None of the above

11-The unit of kinematic viscosity is:

(A) m3/s

(B) m2/s

(C) m/s2

(D) m/s

12-The fluid pressure, exerted upon a column of liquid, can be measured by an instrument called:

(A) Pressure gauge

(B) Venturi meter

(C) Manometer

(D) Energy meter

13-Give an example for positive displacement pump:

(A) Piston pump

(B) Jet pump

(C) Centrifugal pump

(D) Propeller pump

14-Working of orifice meter is based on

(A) Pascal’s law

(B) Bernoulli’s theorem

(C) Stoke’s law

(D) Archimedes principle

15-For a cylindrical pipe of diameter d, the hydraulic mean depth ‘m’ is equal to

(A) 4d

(B) 2d

(C) d/4

(D) d/2

16-Water is flowing with a velocity 4m/s2 in a pipe line of diameter 8 cm. The diameter suddenly reduced to 2 cm, what is its corresponding velocity?

(A) 8 m/s2

(B) 16 m/s2

(C) 32 m/s2

(D) 64 m/s2

17-One stoke is equal to:

(A) 10-4 m2/s

(B) 10-3 m2/s

(C) 10-2 m2/s

(D) 10-1 m2/s

18-Steady flow occurs when:

(A) velocity does not change

(B) pressure does not change

(C) conditions change gradually with time

(D) conditions do not change with time at any point

19-Pressure in Pascal at a depth of 0.5m below the free surface of water will be

(A) 0.5 Pa

(B) 4905 Pa

(C) 9810 Pa

(D) 981 Pa

20-Newtons law of viscosity states:

(A) shear stress is directly proportional to velocity

(B) shear stress is directly proportional to velocity gradient

(C) shear stress is directly proportional to shear strain

(D) shear stress is directly proportional to viscosity

21-The term v2/2g is known as

(A) velocity head

(B) pressure head

(C) potential head

(D) none of the above

22-Notch is a device used for measuring

(A) rate of flow through pipes

(B) rate of flow through small channels

(C) velocity through pipes

(D) velocity through small channels

ANSWERS:

1-(C), 2-(C), 3-(B), 4-(D), 5-(D), 6-(B), 7-(A), 8-(A), 9-(D), 10-(A), 11-(B), 12-(C), 13-(A), 14-(B), 15-(C), 16-(D), 17-(A), 18-(A), 19-(B), 20-(B), 21-(A), 22-(B)