Entropy and Carnot's Engine

Which of the following is not a thermodynamic quantity?

• Pressure

• Temperature

• Charge

• Entropy

An isolated system is one that is

• not touching any object

• contain within adiabatic walls

• inside a vessel having perfectly insulating and rigid walls

• inside a vessel having perfectly rigid walls

The internal energy of a gas is

• the energy due to pressure exerted on the walls of the container

• the sum of kinetic and potential energies of all the molecules

• (3/2)NKT

• equal to rest mass energy of all the molecules

Equation of state of an electrodynamic system is the relationship between

• P and T

• S and T

• U and T

• any three thermodynamic variables of the system

An indicator diagram for a system is

• Relationship of any three variables of the system

• A diagram showing the internal energy of the system

• a diagram between any two thermodynamic variables such that each point represents an equilibrium state

• a diagram that shows an irreversible change occurring in the system

A thermodynamic process in which the volume of the system remains constant is called

• an isobaric process

• an isothermal process

• an adiabatic process

• an isochoric process

in a gaseous system, work done in one cycle of a cyclic process is numerically equal to

• The product of P and V

• The net change in entropy of the system

• the area enclosed by the closed curve representing the P-V diagram

• the area enclosed by the P-T curve

In one cycle a Carnot's heat engine takes place 100 calories of heat from a source and rejects 50 cal to the sink. Its efficiency is

• 100%

• 50%

• 25%

• 15%

Efficiency of Carnot engine

Typical automobile engine

• heating appliance

• thermostat

• refrigerator

• heat engine