Multiple Choice Questions ( MCQ ) for the Power Plant Engineering

1. In an impulse turbine.......
   A.The steam is expanded in nozzles only and there is a pressure drop and heat drop

   B.The steam is expanded both in fixed and moving blades continuously

   C.The steam is expanded in moving blades only

   D.The pressure and temperature of steam remains constant

Ans: A

2. The reheating of steam in a turbine........

A.   Increases the work done through the turbine

   B. Increases the efficiency of the turbine

   C. Reduces wear on the blades

   D. All of the above

Ans: B

3.  De-Laval turbine is a
A. Single rotor impulse turbine

B.  Multi-rotor impulse turbine

C. Impulse reaction turbine

D. None of the above

Ans: A

4. Steam turbine is classified on basis of __________
A. type of blades
B. exhausting condition
C. type of Steam flow
D. all of the mentioned

Ans:D

5. Impulse blades are in the shape of __________
A. Rain drop
B. Circular
C. Half-moon
D. None of the mentioned

Ans: C

6. When steam reaches turbine blades the type of force responsible for moving turbine blades are _____________
A. Axial force
B. Shear force
C. Longitudinal force
D. None of the mentioned

Ans: A

7. Non Condensing steam turbine can also be called as _________
A. Extraction steam turbine
B. Back pressure steam turbine
C. Impulse steam turbine
D. None of the mentioned

Ans: B

8. Based on type of flow arrangements gas turbines are classified into _____________
A.  None of the mentioned
B.  Impulse-reaction gas turbine
C. Open cycle gas turbine
D. Axial flow gas turbine

Ans: D

9. Identify the types of Gas turbines ___________
A. Turbo jet
B. Turboprop
C. Turbo fan
D. All of the mentioned.

Ans: D

10. Gas Turbine Engines when compared to Reciprocating engines have ________
A. high power to weight ratio
B. low power to weight ratio
C. produce low power
D. none of the mentioned

Ans: A

11. For producing same power ____________
A.  reciprocating engines will be smaller when compared to Gas turbine engines
B. gas turbine engines are smaller when compared to reciprocating engine counter parts
C. reciprocating engines are complex
D. none of the mentioned

Ans: B

12. Most preferable Gas turbines are required to be used in _____________
A. fluctuating loads
B. constant loads
C. idling conditions
D. none of the mentioned

Ans: B

13. Gas turbines work on ________
A. Otto cycle
B. Dual cycle
C. Brayton cycle
D. Diesel cycle

Ans: C

14. Gas turbine performance majorly depends on __________
A. compressor efficiency
B. calorific value of fuel used
C. nozzle efficiency
D. none of the mentioned

Ans: A

15. In order to generate energy in Sahara Desert where water is available in significantly low amount. Which system can we employ in such a place:

A. Steam Turbine
B. Gas Turbine
C. Steam Engine
D. Tidal Engine

Ans: B

16. Cross compound steam turbines are once used in _____________
A. generation of electricity
B. marine ships
C. automobiles
D. none of the mentioned

Ans: B

17. A steam turbine with no nozzle is ________________.
A. Reaction turbine
B. Impulse turbine
C. Both of these
D. None of these

Ans: A

18. The pipes carrying the steam are made of__________________.
A. Steel
B. Cast iron.
C. Aluminum
D. Cobalt.

Ans: A

19. The governing principle of steam turbines are________________.
A. Nozzle controls governing
B. Throttle governing
C. Bypass governing
D. All of these

Ans: A

20. The reheat factor in a steam turbine depends on
A Stage efficiency.
B. Initial pressure and temperature.
C. Exit pressure.
D. All of the above.

Ans: D

21. Air- preheater in a steam power plant_____________.
A. Recovers the heat from the flue gases leaving the economizer.
B. Improves combustion rate.
C. Raises the temperature of the furnace gases.
D. All of these.

Ans: D

22. Compounding of steam turbine is done for

A. reducing the work done

B. increasing the rotor speed

C. reducing the rotor speed

D. balancing the turbine

Ans: C

23. In a regenerative feed heating cycle, the greatest economy is affected

A. when steam is extracted from only one suitable point of steam turbine
B. when steam is extracted from several places in different stages of steam turbine
C. when steam is extracted only from the last stage of steam turbine
D. when steam is extracted only from the first stage of steam turbine

Ans: B

24. The modern steam turbines are

A. impulse turbines

B. reaction turbines

C. impulse-reaction turbines

D. none of the above

Ans: C

25.  The pressure on the two sides of the impulse wheel of a steam turbine

A. is same

B. is different

C. increases from one side to the other side

D.decreases from one side to the other side

Ans: A

26.  In De Laval steam turbine

A.The pressure in the turbine rotor is approximately same as in condenser
B.The pressure in the turbine rotor is higher than pressure in the condenser
C.The pressure in the turbine rotor gradually decreases from inlet to exit from condenser

D.None from the above

Ans: A

27. In case of reaction steam turbine

A.There is enthalpy drop both in fixed and moving blades

B.There is enthalpy drop only in fixed blades

C.There is enthalpy drop only in moving blades

D.None of the above

Ans: A

28. Curtis turbine is

A. reaction steam turbine

B. pressure velocity compounded steam turbine

C. pressure compounded impulse steam turbine

D. velocity compounded impulse steam turbine

Ans: B

29. Rateau steam turbine is

A. reaction steam turbine

B. velocity compounded impulse steam turbine

C. pressure compounded impulse steam turbine

D. pressure velocity compounded steam turbine

Ans: C

30. For Parson’s reaction steam turbine, degree of reaction is

A. 75%

B. 100%

C. 50%

D. 60%

Ans: C

31. The blade speed ratio of impulse turbine is given as ___________

A. (Blade velocity) / (Steam velocity at inlet)
B.  (Blade velocity) / (Steam velocity at exit)
C.  (Steam velocity at inlet) / (Blade velocity)
D.  (Steam velocity at exit) / (Blade velocity)

Ans: A

32. The nozzle efficiency can be defined as the ratio of

A. isentropic enthalpy drop to actual enthalpy drop
B. actual enthalpy drop to isentropic enthalpy drop
C. isothermal enthalpy drop to isentropic enthalpy drop
D. isentropic enthalpy drop to isothermal enthalpy drop

Ans: B

33. In an impulse turbine
A. The steam is expanded in nozzles only and there is a pressure drop and heat drop

B.The steam is expanded both in fixed and moving blades continuously

C.The steam is expanded in moving blades only

D.The pressure and temperature of steam remains constant

Ans: A

34. In a reaction turbine

A.The steam is allowed to expand in the nozzle, where it gives a high velocity before it enters the moving blades

B.The expansion of steam takes place partly in the fixed blades and partly in the moving blades

C.The steam is expanded from a high pressure to a condenser pressure in one or more nozzles

D.The pressure and temperature of steam remains constant

Ans: B

35. In impulse turbines, when friction is neglected, the relative velocity of steam at outlet tip of the blade is _________ the relative velocity of steam at inlet tip of the blade.
A. Equal to

B.Less than

C.Greater than

D.None of these

Ans: A