### Hydraulic and Fluid Mechanics

1. Liquids

1. Cannot be compressed
2. Occupy definite volume
3. Are not affected by change in pressure and temperature
4. None of the above

None of the above

2. A balloon lifting in air follows the following principle

1. Law of gravitation
2. Archimedes principle
3. Principle of buoyancy
4. All of the above

All of the above

3. A body floating in a liquid is said to be in neutral equilibrium, if its metacentre

1. Coincides with its centre of gravity
2. Lies above its centre of gravity
3. Lies below its centre of gravity
4. Lies between the centre of buoyancy and centre of gravity

Coincides with its centre of gravity

4. A body floats in stable equilibrium

1. When its meatcentric height is zero
2. When the metacentre is above e.g.
3. When its e.g. is below its center of buoyancy
4. Metacentre has nothing to do with position of e.g. for determining stability

When the metacentre is above e.g.

5. A bucket of water is hanging from a spring balance. An iron piece is suspended into water without touching sides of bucket from another support. The spring balance reading will

1. Increase
2. Decrease
3. Remain same
4. Increase/decrease depending on depth of immersion

Remain same

6. A channel is said to be of most economical cross-section, if

1. It gives maximum discharge for a given cross-sectional area and bed slope
2. It has minimum wetted perimeter
3. It involves lesser excavation for the designed amount of discharge
4. All of the above

All of the above

7. A compound pipe is required to be replaced by a new pipe. The two pipes are said to be equivalent, if

1. Length of both the pipes is same
2. Diameter of both the pipes is same
3. Loss of head and discharge of both the pipes is same
4. Loss of head and velocity of flow in both the pipes is same

Loss of head and discharge of both the pipes is same

8. A compound pipe of diameter d1, d2 and d3 having lengths l1, l2 and l3 is to be replaced by an equivalent pipe of uniform diameter d and of the same length (l) as that of the compound pipe. The size of the equivalent pipe is given by

1. l/d2 = (l2/d22) + (l3/d32)
2. l/d3 = (l2/d23) + (l3/d33)
3. l/d4 = (l2/d24) + (l3/d34)
4. l/d5 = (l2/d25) + (l3/d35)

l/d5 = (l2/d25) + (l3/d35)

9. A differential manometer is used to measure

1. Atmospheric pressure
2. Pressure in pipes and channels
3. Pressure in Venturimeter
4. Difference of pressures between two points in a pipe