Hydraulic Fluid Mechanics MCQs

Question 1

Ratio of inertia force to surface tension is known as

Accepted Answer

Weber's number

Answer

Mach number

Answer

Froude number

Answer

Reynold's number

Question 2

A ship whose hull length is 100 m is to travel at 10 m/sec. For dynamic similarity, at what velocity should a 1:25 model be towed through water ?

Accepted Answer

2 m/sec

Answer

10 m/sec

Answer

25 m/sec

Answer

(a) 50 m/sec

Question 3

A model of a reservior is drained in 4 mts by opening the sluice gate. The model scale is 1: 225. How long 'should it take to empty the prototype ?

Accepted Answer

4 x NEB-minutes.

Answer

900 minutes

Answer

4 x (225)3/2 minutes

Answer

4 (225)1/3 minutes

Question 4

A model of torpedo is tested in a towing tank at a velocity of 25 m/sec. The prototype is expected to attain a velocity of 5 m/sec. What model scale has beep used ?

Accepted Answer

0.045138889

Answer

0.00072338

Answer

0.059027778

Answer

1

Question 5

For a floating body to be in stable equilibrium, its metacentre should be

Accepted Answer

Above the centre of gravity.

Answer

Below the centre of gravity

Answer

Above the centre of buoyancy

Answer

Between e.g. and centre of pressure

Question 6

For a flodingilsody to be in equilibrium

Accepted Answer

A11 of he above

Answer

Meta centre should be above e.g.

Answer

Centre of buoyancy and e.g. must lie on same vertical plane

Answer

A righting couple should be formed

Question 7

Choose the wrong statement

Accepted Answer

All floating bodies are stable.

Answer

The centre of buoyancy is located at the centre of gravity of the displaced liquid

Answer

If e.g. and centre of buoyancy coincide, the submerged body must lie at neutral equilibrium for all positions

Answer

For stability of floating cylinders or spheres, the e.g. of body must lie below the centre of buoyancy

Question 8

Centre of pressure on an inclined plane is

Accepted Answer

Below the centroid

Answer

At the centroid

Answer

Above the centroid

Answer

At metacentre

Question 9

The centre of gravity of the volume of the liquid displaced by an immersed body is called

Accepted Answer

Metacentre

Answer

Centre of gravity

Answer

Centre of pressure

Answer

Centre of buoyancy