Engineering Thermodynamics (3131905) MCQs

MCQs of Vapor Power Cycles

Showing 11 to 20 out of 35 Questions
11.

Rankine efficiency of a steam power plant

(a)

improves in summer as compared to that in winter

(b)

improves in winter as compared to that in summer

(c)

is unaffected by climatic conditions

(d)

none of the mentioned

Answer:

Option (b)

12.

Rankine cycle comprises of ___________.

(a)

two isentropic processes and two constant volume processes

(b)

two isentropic processes and two constant pressure processes

(c)

two isothermal processes and two constant pressure processes

(d)

none of the mentioned

Answer:

Option (b)

13.

 In Rankine cycle, the work output from the turbine is given by ___________.

(a)

 change of internal energy between inlet and outlet

(b)

 change of enthalpy between inlet and outlet

(c)

change of entropy between inlet and outlet

(d)

change of temperature between inlet and outlet

Answer:

Option (b)

14.

Which of the following contributes to the improvement of efficiency of Rankine cycle in a thermal power plant?

(a)

reheating of steam at intermediate stage

(b)

regeneration use of steam for heating Boiler feed water

(c)

use of high pressures

(d)

all of the mentioned

Answer:

Option (d)

15.

What is the actual turbine inlet temperature in Rankine cycle?

(a)

7000C

(b)

8000C

(c)

5500C

(d)

11500C

Answer:

Option (c)

16.

Rankine cycle efficiency of a good steam power plant may be in the range of?

(a)

15 to 20%

(b)

35 to 45%

(c)

70 to 80%

(d)

90 to 95%

Answer:

Option (b)

17.

 The mean temperature of heat addition can be increased by?

(a)

decreasing the amount of heat added

(b)

increase the amount of heat added

(c)

increase condensor pressure

(d)

decreasing turbine inlet temperature

Answer:

Option (c)

18.

Which of the following statement is true?

(a)

efficiency is directly proportional to mean temperature of heat addition

(b)

efficiency is inversely proportional to mean temperature of heat addition

(c)

efficiency is exponential function of mean temperature of heat addition

(d)

efficiency does not depend on mean temperature of heat addition

Answer:

Option (a)

19.

Why reheating of steam is used?

(a)

to increase efficiency

(b)

to increase work output

(c)

to increase Turbine Inlet Temperature

(d)

to reduce amount of fuel used

Answer:

Option (b)

20.

What is the effect of reheat on steam quality?

(a)

increases

(b)

decreases

(c)

does not change

(d)

depends on several parameters

Answer:

Option (a)

Showing 11 to 20 out of 35 Questions