Heat Engine, Refrigerator, and Heat Pump Principles

Which law of thermodynamics is concerned with the conservation of energy?

First Law

What does the First Law of Thermodynamics alone not guarantee regarding a process?

Occurrence of the process

Which concept is NOT explained by the First Law of Thermodynamics?

Spontaneity of a process

Why is heat transfer from a low temperature body to a high temperature body practically infeasible?

It violates the Second Law of Thermodynamics Signup and view all the answers

Which law addresses the spontaneity of a thermodynamic process?

Second Law Signup and view all the answers

What is one aspect that the First Law of Thermodynamics allows but is not practically feasible?

Heat transfer from cold to hot without work Signup and view all the answers

In which type of process does irreversibility occur?

When heat is delivered to surroundings Signup and view all the answers

Which of the following is an example of an irreversible process?

Plastic deformation Signup and view all the answers

What is the main factor affecting the efficiency of a heat-engine cycle?

The temperature difference between the reservoirs Signup and view all the answers

Why can't reversible cycles be achieved in practice?

Because the irreversibilities associated with each process cannot be eliminated Signup and view all the answers

What was Sadi Carnot's contribution to improving practical heat engines?

Proposing the Carnot cycle with the highest possible efficiency Signup and view all the answers

Which process allows molecules to blend from a region of high concentration to low concentration?

"Free expansion" due to low pressure Signup and view all the answers

What is the main function of a heat engine?

Convert thermal energy into mechanical energy Signup and view all the answers

In a heat engine, where is heat absorbed from?

Hot reservoir Signup and view all the answers

Which device removes heat from a low-temperature source?

Refrigerator Signup and view all the answers

What is the primary function of a heat pump?

Transfer heat from low-temperature to high-temperature Signup and view all the answers

How does a refrigerator differ from a heat engine?

A refrigerator operates in the opposite direction to a heat engine Signup and view all the answers

What is the function of a sink in the context of heat transfer?

Absorb energy in the form of heat Signup and view all the answers

What characterizes a spontaneous process in thermodynamics?

Driven by tendency towards a state of greater thermal equilibrium Signup and view all the answers

What distinguishes a non-spontaneous process from a spontaneous one?

Requires energy input to occur Signup and view all the answers

Why might a non-spontaneous process occur even when the system lacks sufficient energy?

Driven by changes in pressure Signup and view all the answers

What does the second law of thermodynamics declare about certain processes?

Certain processes are impossible even if they don't violate the first law Signup and view all the answers

Which hypothetical body has a large thermal energy capacity and can supply or absorb heat without temperature change?

Thermal Energy Reservoir Signup and view all the answers

What principle does the second law of thermodynamics place constraints upon?

Direction of heat transfer and efficiency of heat engines Signup and view all the answers

What is the formula for calculating cycle efficiency?

$1 - \frac{T_H}{T_L}$ Signup and view all the answers

What does Carnot efficiency describe?

Maximum thermal efficiency achievable by a heat engine Signup and view all the answers

Who is credited with finding that all reversible heat engines operating between the same two temperatures have the same thermal efficiency?

Sadi Carnot Signup and view all the answers

What is needed to calculate the Carnot efficiency?

Absolute temperatures of the source and sink Signup and view all the answers

What is true about the thermal efficiency of actual heat engines compared to the Carnot efficiency?

They are always less than Carnot efficiency Signup and view all the answers

Which cycle is associated with the Carnot heat engine?

Carnot cycle Signup and view all the answers