AP PHYSICS II EXAM REVIEW: Chapter 18- The Laws of Thermodynamics

800J

A certain gas is compressed adiabatically. The amount of work done on the gas is 800J. What is the change in internal energy of the gas?

Three times as large as the inital value

A monatomic ideal gas is compressed isothermally to one-third of its initial volume. The resulting pressure will be...

.0037m^3

A system consisting of an ideal gas at the constant pressure of 101kPa gains 920J of heat. Find the change in volume of the system if the internal energy of the gas increases by 550J.

-1075kJ

An athlete doing push-ups performs 650kJ of work and loses 425 kJ of heat. What is the change in the internal energy?

If the pressure increases in proportion to the volume

An ideal monatomic gas undergoes a reversible expansion to 1.5 times its original volume. In which of these processes does the gas perform the most work?

increases

An ideal monatomic gas undergoes an isothermal expansion. It is correct to affirm that its entropy...

Standard engine efficiency depends on the amount of heat in the system while Carnot's max efficiency depends on the temperature.

Describe the difference between standard engine efficiency and Carnots max efficiency?

True

Entropy is a state function. (T/F)

It must be possible to restore both the system and the surroundings to their original states.

If a system undergoes a reversible process...

True

If a thermometer measures the temperature of two objects as being equal, you can conclude that if the objects are placed in thermal contact, no heat will flow between them. (T/F)

The gas must release heat to its surroundings

In a given reversible process, the temperature of an ideal gas is kept constant as the gas is compressed to a smaller volume. Select the true statement from among the following:

False

In the first law of thermodynamics, W is the work done on the system, W is positive if work is done on the system. (T/F)

Yes, by freezing water to make an ice cube, the entropy of the water decreased. But looking in terms of the universe, the entropy increased. This is because the heat the freezer let out increased the entropy of the universe; therefore, this system did not violate the 2nd law of thermodynamics.

Is it possible to decrease the entropy of a system? If so does this violate the 2nd law of thermodynamics?

True

Neither heat nor work are state functions. (T/F)

No it will not because the "engine" itself will create heat through the work it takes to move energy from the cold reservoir to the hot reservoir. Basically, W is creating net heat because Qc and Qh are the same, and Qc=Qh+W. Therefore, the overall temperature of the kitchen will increase.

On a hot day, you open the fridge and experience a refreshing feeling when the cool air comes in contact with your body. You think to yourself "I think that I'll just keep the fridge door open and stand in front of the fridge all day to stay cool." Will this work?

True

Order in one part of the universe can only be produced at the expense of disorder in another part. (T/F)

False

The entropy of a system remains constant during an adiabatic change even if the change is irreversible. (T/F)

The universe will reach thermal equilibrium

What is meant by the heat death of the universe?

The internal energy of the gas decreases

When a gas expands adiabatically...

Temperature to the one with the lower temperature

When objects at different temperatures are brought into thermal contact with one another, the resulting spontaneous flow of heat proceeds from the object with the higher...

It is impossible to lower the temperature of an object to absolute zero in a finite number of steps.

Which of the following is a statement of the third law of thermodynamics?