Engineering Thermodynamics MCQs

Question 1

For the same compression ratio, the efficiency of Diesel cycle is __________ Otto cycle.

Accepted Answer

Less than

Answer

Greater than

Answer

Equal to

Answer

None of these

Question 2

Diesel cycle consists of __________ processes.

Accepted Answer

One constant pressure, one constant volume and two isentropic

Answer

Two constant volume and two isentropic

Answer

Two constant pressure and two isentropic

Answer

Two constant volume and two isothermal

Question 3

When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel, the process is known as __________ of fuel.

Accepted Answer

Carbonization

Answer

Atomization

Answer

Combustion

Answer

None of these

Question 4

The throttling process is __________ process.

Accepted Answer

Irreversible

Answer

Reversible

Answer

Reversible or irreversible

Answer

None of these

Question 5

The atomic mass of nitrogen is __________ oxygen.

Accepted Answer

Less than

Answer

Equal to

Answer

More than

Answer

None of these

Question 6

A tri-atomic molecule consists of __________ atoms.

Accepted Answer

Three

Answer

One

Answer

Two

Answer

Four

Question 7

Kelvin-Planck’s law deals with

Accepted Answer

Conversion of heat into work

Answer

Conservation of work

Answer

Conservation of heat

Answer

Conversion of work into heat

Question 8

The thermal efficiency of an ideal gas turbine plant is given by (where r = Pressure ratio)

Accepted Answer

$$1 - {\left( {\frac{1}{{	ext{r}}}} ight)^{\frac{{\gamma - 1}}{\gamma }}}$$

Answer

$${{	ext{r}}^{\gamma - 1}}$$

Answer

$$1 - {{	ext{r}}^{\gamma - 1}}$$

Answer

$$1 - {\left( {\frac{1}{{	ext{r}}}} ight)^{\frac{\gamma }{{\gamma - 1}}}}$$

Question 9

A manufacturer claims to have a heat engine capable of developing 20 h.p. by receiving heat input of 400 kcal/mt and working between the temperature limits of 227°C and 27°C. His claim is

Accepted Answer

Not possible

Answer

Theoretically possible

Answer

May be possible with lot of sophistications

Answer

Cost will be very high