FMHM & Hydraulics chapter 2

 

Liquid pressure and its mesurment

1. Which one of the following is the dimension of pressure?
a) [MLT²].
b) [MLT^-2].
c) [ML^-1T²].
d) [ML^-1T^-2].

Answer D

2. If the displacement is measured with strain gauge then the number of strain gauge normally required are
A. One
B. Two
C. Three
D. Four

Answer: D

3. What is the pressure in Pascals at a depth of 1m below the water surface?
a) 98100 Pa
b) 980 Pa
c) 98 Pa
d) 1 Pa

Answer: a

4. 15 bar equals to __________ Pascals.
a) 10⁵Pa
b) 1.5 x 10⁶ Pa
c) 100 Pa
d) 1000 Pa

Answer: b

5. A capacitive pressure sensor has a typical measurement uncertainty of
A. ± 0.2%
B. ± 0.4%
C. ± 0.1%
D. ± 0.8%

Answer: A.

6. Which one of the following statements is true regarding pressure?
a) Pressure is a scalar quantity
b) Pressure is a vector quantity
c) Pressure is a scalar quantity only when the area is infinitesimally small
d) Pressure is a vector quantity only when the area is infinitesimally small

Answer: a

7. The right limb of a simple U-tube manometer containing mercury is open to the atmosphere while the lift limb is connected to a pipe in which a fluid of specific gravity 0.85 is flowing. The centre of the pipe is 14 cm below the level of mercury in the right limb.Evaluate the pressure of fluid flowing in the pipe if the difference of mercury level in the two limbs is 22 cm.

a) 2.86 N/cm²

b) 5.73 N/cm²

c) 1.43 N/cm²

d) None of the mentioned

Answer: a

8. What type of liquids are measured using a manometer?
a) Heavy liquids
b) Medium Liquids
c) Light Liquids
d) Heavy and light liquids

Answer: c

9. A single coloumn manometer is connected to a pipe containing a liquid of specific gravity 0.75. Find the pressure in the pipe if the area of reservoir is 250 times the area of tube for the manometer reading. The difference in mercury level is 40 cm. On the left limb the fluid is upto the height of 20 cm.
a) 10.42 N/cm²
b) 5.21 N/cm²
c) 2.60 N/cm²
d) None of the mentioned

Answer: b

10. The instruments used for the measurement of pressure is/are
A. Bellows
B. Diaphragms
C. Fiber optic pressure sensors
D. All of these

Answer: D

11. A Differential manometer is connected at the points A and Bat the centre of two pipes. The pipe A(left limb) contains a liquid of specific gravity = 1.5 while pipe B (right limb)contains a liquid of specific gravity 0.85. The pressure at A and B are .5 kgf/cm² and 1.2 kgf/cm2 respectively. Find the difference in level of mercuru in the differential manometer. A is 2.5m above B and 5 m above the mercury in its own limb. B is 2.5 m above the mercury level in limb A.
a) 12.7 cm
b) 25.5 cm
c) 6.28 cm
d) 10.85 cm

Answer: a

12. In the inverted U-tube Differential manometer, how is the specific gravity of manometric fluid used relative to the fluid flowing in the pipes
a) Specific gravity is more than that of fluid flowing in pipes
b) Specific gravity is less than that of fluid flowing in pipes
c) Specific gravity is equal to that of fluid flowing in pipes
d) None of the mentioned

Answer: b

13. Manometers are the pressure measuring devices which use the principle of dynamic pressure to measure the pressure difference.
a) True
b) False

Answer: b

15. The distance moved by liquid will be more in which type of manometer?
a) Inclined Single column manometer
b) Vertical Single column manometer
c) Horizontal Single column manometer

d) None of the mentioned

Answer: a

16. Bordon tube is used for the measurement of gauge pressure of
A. Gas
B. Liquid fluid
C. Solid
D. Both (a) and (b)

Answer: D

17. How do we measure the flow rate of liquid?
a) Coriolis method
b) Dead weight method
c) Conveyor method
d) Ionization method

Answer: a

18. What is the viscosity of water at 30^oC?
a) 80.1
b) 0 .801
c) 801
d) 0.081

Answer: b

19. Dead weight gauge is used for the measurement of pressure of
A. About 1000 bar
B. About 2000 bar
C. About 5000 bar
D. About 7000 bar
Answer D

20. Which device is popularly used for measuring difference of low pressure?
a) Inverted U-tube Differential Manometer
b) U-tube Differential Manometer
c) Inclined Single column manometer
d) Vertical Single column manometer

Answer: a

21. Define Viscosity?
a) Resistance to flow of an object
b) Resistance to flow of air
c) Resistance to flow of fluid
d) Resistance to flow of heat

Answer: c

22. The ionization gauge an instrument used for the measurement of
A. Very low pressure
B. Medium pressure
C. High pressure

D. Very high pressure

Answer: A

23. The device used to measure the fluid pressure is _____________
a) Hygrometer
b) Calorimeter
c) Manometer
d) Thermometer

Answer: c

24. When visual indication of pressure level is required then the instrument generally used is
A. Monometers
B. Diaphragm sensors
C. Bourdon tube
D. Resonant wire device
Answer: A

 

25. What is the instrument used for the automatic control scheme during the fluid flow?
a) Rota meters
b) Pulley plates
c) Rotary Piston
d) Pilot Static Tube

Answer: d

26. For the measurement of high pressure with high accuracy the device used is
A. Manganin wire pressure
B. Ionization gauge
C. Dead weight gauge
D. Bordon tubes

Answer: A

27. Advantage of passive instrument is
A. It does not need power supply
B. Cheap
C. Sensitive
D. Accurate

ANSWER: A.

 

28. The pressure at any given point of a non-moving fluid is called the ____________
a) Gauge Pressure
b) Atmospheric Pressure
c) Differential Pressure
d) Hydrostatic Pressure

Answer: d

29. Which among these devices are the best suited for the measurement of high pressure liquids with high accuracy?
a) Dead Weight Gauge
b) Vacuum Gauge
c) Manganin wire pressure
d) Ionization Gauge
Answer: c