ME2345 Exam 2 preparation quiz

The boundary work of a substance in a rigid tank is always zero.

• True

• False

Enthalpy is the combination of internal energy and boundary work.

• True

• False

The coefficient of performance (COP) is a measure of efficiency for engines and powerplants.

• True

• False

An example of a thermal sink is:

• A refrigerator.

• The sun.

• An engine.

• The atmosphere.

An example of an open, steady-state system is:

• A piston-cylinder.

• A nozzle.

• A blender.

• An emptying tank.

A heat pump and a refrigerator are essentially the same cycle.

• True

• False

The net energy change of a cycle is always zero.

• True

• False

The net power output of a cycle is always zero.

• True

• False

The efficiency of a cycle must always be less than that of the Carnot cycle.

• True

• False

A polytropic process with n → infinity will be:

• Isochoric.

• Isobaric.

• Adiabatic.

• Isothermal.