TaAP - Energy

Heat is transferred as a result of a:

• pressure difference.

• body force.

• entropy difference.

• temperature difference.

For a closed system, energy can be transferred across the boundary via heat and work transfer.

• True.

• False.

A non-flow system loses 48 kJ of heat and receives 82 kJ as work. What is the change in internal energy of the fluid?

• -34 kJ

• 34 kJ

• 130 kJ

• -130 kJ

For a thermodynamic cycle, the net work done during a cycle is equal to zero.

• True.

• False.

Answer explanation

For a thermodynamic cycle, the net work done during a cycle is equal to the net heat transfer. The net change in total energy is zero.

Consider flow through a well-insulated nozzle. Which of the terms in the Steady Flow Energy Equation can be considered negligible?

• Heat transfer and the change in kinetic energy.

• Work transfer, heat transfer and the change in enthalpy.

• Work transfer and the change in kinetic energy.

• Work transfer, heat transfer and the change in potential energy.

Answer explanation

deltaKE + deltaH = 0

Consider flow through a well-insulated turbine. Which of the terms in the Steady Flow Energy Equation can be considered negligible?

• Heat transfer, the change in kinetic energy, and the change in potential energy. 

• Heat transfer, the change in potential energy, and the change in enthalpy.

• Work transfer, heat transfer and the change in kinetic energy.

• Work transfer and the change in potential energy.

Internal energy is:

• The energy that a system possesses as a result of its motion.

• The energy that a system possesses as a result of its elevation in a gravitational field.

• The sum of microscopic forms of energy including sensible energy, latent energy, chemical energy and nuclear energy.

• The sum of all forms of the macroscopic energies.