1. The flow rate through a circular pipe is measured by
- pitot-tube
- venturimeter
- orifice meter
- none of the above
Code:
- i
- i, ii and iii
- ii and iii
- all of the above
2. The head loss is more in a
- venturimeter
- nozzle meter
- inclined venturimeter
- orifice meter
3. The loss of energy in orifice meter is more than in the case of venturimeter because of
- Sudden obstruction
- Turbulence
- pressure variation
- More friction
4. Orifices are used to measure
- rate of flow
- velocity
- pressure
- none of three mentioned here
5. In a standard orifice meter,
- the level edge is on the upstream
- the coefficient of discharge does not depend upon the location of taps
- the loss of head is less than that in a venturimeter
- the level angle is usually 30° to 45°
6. An orifice is called a large orifice if water head, is
- twice the diameter of the orifice
- thrice the diameter of the orifice
- four times the diameter of the orifice
- five times the diameter of the orifice
7. Two small orifices A and B of diameter 1 cm and 2 cm respectively, are placed on sides of a tank at depths of h1 and h2 below the open liquid surface. If discharges through A and B are equal, then ratio of h1 and h2 (assuming equal cd values) will be
- 16 : 1
- 8 : 1
- 4 : 1
- 2 : 1
8. In a short cylindrical external mouthpiece, the vena-contracta occurs at a distance from the outlet of orifice equal to
- Diameter of the orifice
- One-fourth the diameter of the orifice
- One-third the diameter of the orifice
- Two-third the diameter of the orifice
- Two times the diameter of the orifice
9. Coefficient of discharge in terms of orifice is, actual discharge ‘a’ and ideal discharge ‘d’ is
- a/d
- d/a
- (a + d)/d
- (a – d)/d
10. The coefficient of discharge for an external mouthpiece depends upon
- Velocity of liquid
- Pressure of liquid
- Area of mouthpiece
- Length of mouthpiece
11. Which mouthpiece has the maximum coefficient of discharge?
- External mouthpiece
- Convergent divergent mouthpiece
- Internal mouthpiece
- None of the above
12. A convergent mouth piece has the maximum value of coefficient of discharge (C) is about
- 0.60
- 0.95
- 0.50
- 0.80
13. The average value of coefficient of velocity is
- 0.76
- 0.84
- 0.62
- 0.97
14. Consider the following devices:
- Orifice
- Borda’s mouthpiece running free
- Bell-mouthed orifice
- External mouthpiece
What is the correct sequence of these devices in decreasing magnitude of coefficient of discharge?
- ii, iii, i, iv
- iv, iii, i, ii
- iv, i, iii, ii
- ii, i, iii, iv
15. Mouthpiece has increased net head when compared to small orifice due to
- turbulence in the tube
- vena contracta occurred within the tube
- smaller length of the tube
- smooth boundary of the tube
16. A mouthpiece and an orifice, both of the same diameter ‘d’, are discharging under the same head ‘H’. The discharge through the mouthpiece will be
- the same as that of the orifice
- less than that of the orifice
- more than that of the orifice
- no relationship
17. At vena contracta, the area of the water jet is minimum and the velocity of emerging water is
- minimum
- average
- maximum
- zero
18. An orifice discharges under a head of 1.25m of water. A pitot tube kept at its centre line at the vena contracta indicates a head of 1.20 m of water. The coefficient of velocity of the orifice is
- 0.980
- 0.990
- 0.965
- 0.9565
19. A vertical cylindrical tank, 2 m diameter has, at the bottom, a 5 cm diameter, sharp-edged orifice, for which Cd = 0.6. Water enters the tank at a constant rate of 9 l/sec. At what depth above the orifice will the level in the tank become steady?
- 2.95 m
- 2.75 m
- 2.60 m
- 2.50 m
20. The ratio of velocity of flow at exit to theoretical velocity of jet corresponding to manometric head is known as
- Specific speed
- Flow ratio
- Speed ratio
- Hydraulic ratio
21. The coefficient of discharge, Cd in terms of Cv and Cc is given (Notations have their usual meaning)
- Cv = Cd × Cc
- Cc = Cd × Cv
- Cd = Cc × Cv
- Cd = Cc – Cv
22. The height of water level in a tank above the centre of a circular hole 2.5 cm in diameter is 50m. The velocity of water flowing through the hole is (neglect friction between jet and wall)
- 25.85 m/sec
- 20.53 m/sec
- 40.40 m/sec
- 31.32 m/sec