Practice Test: Question Set - 16
1. The air pressure at the fuel bed is reduced below that of atmosphere by means of a fan placed at or near the bottom of the chimney to produce a draught. Such a draught is called
- (A) Natural draught
- (B) Induced draught
- (C) Forced draught
- (D) Balanced draught
2. The dry saturated steam at very low pressure, (510 kg/cm²) when throttled to atmosphere will become
- (A) Wet
- (B) Superheated
- (C) Remain dry saturated
- (D) Dry
3. The nozzle efficiency is the ratio of
- (A) Workdone on the blades to the energy supplied to the blades
- (B) Workdone on the blades per kg of steam to the total energy supplied per stage per kg of steam
- (C) Energy supplied to the blades per kg of steam to the total energy supplied per stage per kg of steam
- (D) None of the above
4. All steam engines work on
- (A) Zeroth law of thermodynamics
- (B) First law of thermodynamics
- (C) Second law of thermodynamics
- (D) None of these
5. The increase in pressure
- (A) Lowers the boiling point of a liquid
- (B) Raises the boiling point of a liquid
- (C) Does not affects the boiling point of a liquid
- (D) Reduces its volume
6. If the critical pressure ratio for steam is 0.546, then the steam is initially
- (A) Wet steam
- (B) Dry saturated steam
- (C) Superheated steam
- (D) None of these
7. The amount of water evaporated from feed water at _________ into dry and saturated steam at 100° C at normal atmospheric pressure is called equivalent evaporation from and at 100° C.
- (A) 0°C
- (B) 40°C
- (C) 60°C
- (D) 100°C
8. The high pressure boiler is one, which produces steam at a pressure more than
- (A) Atmospheric pressure
- (B) 5 kg/cm²
- (C) 10 kg/cm²
- (D) 7580 kg/cm²
9. The critical pressure ratio for gases is
- (A) 0.528
- (B) 0.546
- (C) 0.577
- (D) 0.582
10. Which of the following is correct? (Where pa = Actual mean effective pressure, pm = Theoretical mean effective pressure, and K = Diagram factor)
- (A) pa= pm/K
- (B) pa= pm × K
- (C) pa= K/pm
- (D) pa= pm + K
11. A stage, in reaction turbine, is represented by
- (A) Number of casing
- (B) Number of entries of steam
- (C) Number of exits of steam
- (D) Each row of blades
12. In a steam engine, superheated steam from the boiler is fed into the steam chest at a pressure of
- (A) 10 atmospheres
- (B) 20 atmospheres
- (C) 30 atmospheres
- (D) 40 atmospheres
13. The diameter of tubes for natural circulation boiler as compared to controlled circulation boilers is
- (A) More
- (B) Less
- (C) Same
- (D) Could be more or less depending on other factors
14. When the inlet pressure of steam is equal to the exit pressure, then
- (A) There is a pressure drop in the nozzle
- (B) Fluid flows through the nozzle
- (C) Pressure drops and fluid flows through the nozzle
- (D) There is no pressure drop and fluid does not flow through the nozzle
15. In water tube boilers
- (A) Water passes through the tubes which are surrounded by flames and hot gases
- (B) The flames and hot gases pass through the tubes which are surrounded by water
- (C) Forced circulation takes place
- (D) None of these