Thermal Energy and Mechanical Work

What is the function of a heat engine?

a) Converts mechanical work into thermal energy.

b) Converts thermal energy into mechanical work.

c) Manages the mechanical work without energy conversion.

d) Manages the thermal energy without work conversion.

b

True or False: According to the second law of thermodynamics, the efficiency of a heat engine could be 100%.

False

What is the role of a working substance in a heat engine?

a) Absorbs heat, does work by expanding, and gives off heat.

b) Provides heat energy to the system from a high-temperature reservoir.

c) Acts as a low temperature reservoir where heat is released.

d) Maintains a constant temperature throughout the engine cycle.

a) Absorbs heat, does work by expanding, and gives off heat.

True or False: The source of a heat engine is a low-temperature reservoir where the working substance releases its heat.

False

Which of the following is commonly used as a working substance in a heat engine?

a) Electricity.

b) Gas.

c) Metal.

d) Wood.

b) Gas.

Which statement best describes the correlation between thermal energy and the movement of particles in a system?

a) Thermal energy decreases as particle movement increases.

b) Thermal energy remains constant as particle movement decreases.

c) Thermal energy increases as particle movement decreases.

d) Thermal energy increases as particle movement increases.

d) Thermal energy increases as particle movement increases.

Complete the sentence: A heat engine operates in a cycle to maximise the efficiency of converting thermal energy to…

a) speed.

b) electrical energy.

c) mechanical work.

d) chemical energy.

c) mechanical work.

True or False: Isothermal processes in a heat engine allow the system to do work without any temperature change.

True

True or False: During adiabatic compression in a heat engine, heat is added to the system to increase the internal energy of the gas.

False

Which component of a heat engine is typically at a higher temperature and provides heat energy to the system?

a) The sink.

b) The fuel.

c) The working substance.

d) The source.

d) The source.

At which stage of the heat engine cycle does the system expand and do work on the surroundings without gaining heat?

a) Isothermal expansion.

b) Adiabatic expansion.

c) Isothermal compression.

d) Adiabatic compression.

b) Adiabatic expansion.