Engineering Thermodynamics (3131905) MCQs

MCQs of Gas Power Cycles

Showing 11 to 20 out of 37 Questions
11.

The efficiency of Diesel cycle approaches to Otto cycle efficiency when

(a)

cut-off is increased

(b)

cut-off is decreased

(c)

cut-off is zero

(d)

cut-off is constant

Answer:

Option (c)

12.

The efficiency of Diesel cycle increases with

(a)

decrease in cut-off

(b)

increase in cut-off

(c)

constant cut-off

(d)

none of these

Answer:

Option (a)

13.

The efficiency of Diesel cycle depends upon

(a)

temperature limits

(b)

pressure ratio

(c)

compression ratio

(d)

cut-off ratio and compression ratio

Answer:

Option (d)

14.

For the same compression ratio, the efficiency of dual combustion cycle is

(a)

greater than Diesel cycle and less than Otto cycle

(b)

less than Diesel cycle and greater than Otto cycle

(c)

greater than Diesel cycle

(d)

less than Diesel cycle

Answer:

Option (a)

15.

Which of the following is the correct statement?

(a)

For a given compression ratio, both Otto and Diesel cycles have the same efficiency

(b)

For a given compression ratio, Otto cycle is more efficient than Diesel cycle

(c)

For a given compression ratio, Diesel cycle is more efficient than Otto cycle

(d)

The efficiency of Otto or Diessel cycle has nothing to do with compressioin ratio.

Answer:

Option (b)

16.

For the same maximum pressure and temperature

(a)

Otto cycle is more efficient than Diesel cycle

(b)

Diesel cycle is more efficient than Otto cycle

(c)

Dual cycle is more efficient than Otto and Diesel cycles

(d)

Dual cycle is less efficient than Otto and Diesel cycles

Answer:

Option (b)

17.

For the constant pressure and heat input, the air standard efficiency of gas power cycle is in the order

(a)

Dual cycle, Diesel cycle, Otto cycle

(b)

Otto cycle, Diesel cycle, Dual cycle

(c)

Dual cycle, Otto cycle, Diesel cycle

(d)

Diesel cycle, Otto cycle, Dual cycle

Answer:

Option (a)

18.

The efficiency of the dual combustion cycle for the same compression ratio, is __________ Diesel cycle.

(a)

greater than

(b)

less than

(c)

equal to

(d)

all of these

Answer:

Option (a)

19.

The gas turbine works on

(a)

Rankine cycle

(b)

Otto cycle

(c)

Carnot cycle

(d)

Brayton cycle

Answer:

Option (d)

20.

Brayton cycles processes are

(a)

Two isentropic and two constant volume

(b)

One constant pressure, one constant volume, two adiabatic

(c)

Two isentropics and two constant pressure

(d)

Two isothermals constant volume a constant pressure

Answer:

Option (b)

Showing 11 to 20 out of 37 Questions