If a heat engine gives an output of 3 kW and input is 10,000 J/s the thermal efficiency of the engine will be
A.30%
B.33.30%
C.66.60%
D.70%
E.100%
Category: Thermodynamics Mcqs
The number of degrees of freedom in case of triatomic gases is
A.2
B.3
C.4
D.5
E.6
The ratio of the rise in temperature of a gas when compressed adiabatically to that when compressed isothermally to the same extent is
A.More than 1
B.Less than 1
C.Equal to 1
D.Depends on the gas
The cycle generally used for gas turbines is
A.Otto cycle
B.Dual cycle
C.Carnot cycle
D.Rankine cycle
E.Brayton cycle
If a surface is elastically hit by N balls each of mass M, moving with same velocity V, the force on the surface will be
A.MNV
B.2 MNV
C.2 MNV2
D.4 MNV
The fastest moving gas molecules are those of
A.Nitrogen
B.Oxygen
C.Chlorine
D.Hydrogen
Clog point of an oil is
A.The point of maximum contamination of oil
B.The level of impurities beyond which oil ceases to flow
C.The temperature at which oil solidifies
D.The temperature at which paraffin and waxes in oil start precipitating
E.None of the above
Which of the following is not a characteristic of liquid air?
A.It has no surface tension
B.It will freeze mercury and ammonia
C.It will cause rubber to become brittle
D.It will separate out lead from solder
If a process can be stopped at any stage and reversed so that the system and surroundings are exactly restored to their initial states, it is known as
A.Adiabatic process
B.Isothermal process
C.Reversible process
D.Thermodynamic process
E.Ideal process
At critical point the latent enthalpy of vaporisation is
A.Only depends on temperature
B.Zero
C.Maximum
D.Minimum
E.None of the above
