# Manometer MCQ – Fluid Mechanics

1. Pressure of a fluid is measured by a

1. barometer
2. manometer
3. lactometer
4. thermometer
5. submerged height

2. The liquid used in manometers should have

1. low density
2. high density
3. low surface tension
4. high surface tension

3. Manometers are used to measure

1. pressure in water channels, pipes, etc.
2. difference in pressure at two points
3. atmospheric pressure
4. very low pressure

4. Micro-manometer is used to

1. determine low pressure difference
2. determine higher pressure difference
3. pressure measurement for gases only
4. measure pressure in congested areas

5. The difference in pressure head, measured a mercury water differential manometer for 20 cm difference of mercury will be

1. 2.52 m
2. 2.72 m
3. 0.2 m
4. 2.0 m

6. Mercury is generally used in manometers for measuring

1. low pressure accurately
2. large pressure only
3. all pressures except the small ones
4. very low pressure

7. The reading on a differential manometer containing mercury (specific gravity= 13.6) is 25 cm. If mercury is replaced with water, the reading on differential manometer would be

1. 3.15 m
2. 3.4 m
3. 34 m
4. 31.5 cm

8. A differential manometer is used to measure

1. pressure in Venturimeter
2. difference of pressure between two points in a pipe
3. atmospheric pressure
4. pressure in pipes

9. Multi U-tube manometers with different fluids are used to measure

1. very low pressure
2. low pressure
3. medium pressure
4. high pressure

10. If a mercury-oil differential manometer shows a 20 cm difference of mercury level, the difference in the pressure head is (consider the specific gravity of oil = 0.8)

1. 2.0 m of oil
2. 2.5 m of oil
3. 3.2 m of oil
4. 4.2 m of oil

11. Air flows through a duct, and the Pitot-static tube measuring the velocity is attached to a differential manometer containing water. If the deflection of the manometer is 100mm, assuming the density 0f air is constant and equals to 1.22 kg/m3, and that the coefficient of the tube is 0.98. The air velocity will be

1. 4.07 m/s
2. 0.393 m/s
3. 39.3 m/s
4. 3.93 m/s

12. The reading of differential manometer of a venturimeter, placed at 45° to the horizontal is 11 cm. If the venturimeter is turned to horizontal position, the manometer reading will be

1. 0
2. 11 cm
3. cm
4. cm

13. A horizontal pipe line conveys a constant rate of flow which is measured by venturimeter installed on it. When the pipe is inclined upwards in the direction of flow, the reading of level difference on a differential U-tube manometer

1. will increase
2. will remain same
3. will decrease
4. may fluctuate with time