Top 350+ Solved Thermodynamics MCQ Questions Answer
Q. For maximum specific output of a constant volume cycle
a. The working fluid should be air
b. The speed should be high
c. Suction temperature should be high
d. Temperature of the working fluid at the end of compression and expansion should be equal
e. Exhaust pressure should be high
Q. A frictionless heat engine can be 100% efficient only if its exhaust temperature is
a. Equal to its input temperature
b. Less than its input temperature
c. 0?K
d. ?100?C
e. 0?C
Q. In steam tables, the entropy is shown as zero for
a. saturated liquid at 0?C
b. saturated vapours at atmospheric pressure
c. Pulsejet
d. saturated vapour at 0?C
e. saturated liquid at atmospheric pressure
Q. When a gas is to be stored, the type of compression that would be ideal is
a. Isothermal
b. Adiabatic
c. Polytropic
d. Constant pressure
e. None of the above
Q. Diffusion is
a. Mixing of two portions of fluid
b. Mixing of a gas in two containers at different pressures
c. Mixing of two portions of a fluid at different temperatures
d. Mixing of unlike fluids
e. None of the above
Q. In case the temperature of a hot body is increased by 50%, the amount of radiation emitted by it would increase by nearly
a. 250%
b. 500%
c. Pulsejet
d. 50%
e. 125%
Q. The efficiency of cycle would be
a. 66.7 percent
b. 100 percent
c. 88.8 percent
d. 37.7 percent
e. 78.3 percent
Q. If the temperature of the sink is decreased, the efficiency of a Carnot engine
a. remain unaffected
b. first increased and then decreases
c. Pulsejet
d. decreases
e. increases
Q. When a gas is to be stored, the type of compression that would be ideal is
a. Isothermal
b. Adiabatic
c. Polytropic
d. Constant volume
e. None of the above
Q. According to Lussac's law for perfect gases, the absolute pressure of given mass varies directly as
a. Temperature
b. Absolute temperature
c. Absolute temperature in case the volume remains constant
d. The product of volume and absolute temperature
e. None of the above
Q. Gibbs free energy G is given by
a. G = T . H . s.
b. G = H/Ts
c. Pulsejet
d. G = H - Ts
e. G = H + Ts
Q. A sterling cycle consists of
a. Two isothermal and two adiabatic processes
b. Two constant volume and two constant pressure processes
c. Two adiabatic and two isentropic processes
d. Two isothermal and two constant volume processes
e. Two adiabatic and two constant pressure processes
Q. A reversible process requires that
a. Newton's law of viscosity be satisfied
b. There whould be no viscous or coulomb friction in the system
c. Heat transfer occurs from surrounding to system only
d. Temperature of system and surroundings be equal
e. There be no heat transfer
Q. The area of pv diagram for a Carnot cycle represents
a. Enthalpy drop
b. Volume and pressure ratios.
c. Temperature drop
d. Work done
e. Total heat supplied
Q. An adlabatic wall permits
a. Heat exchange by all the three modes of heat transfer
b. No heat exchange
c. Radiation heat flow only
d. Convective heat flow only
e. Conduction heat flow only