Thermodynamics

Question 1

Temperature

Answer 1

A measure of how much kinetic energy is in a system.

Question 2

Heat Transfer, Thermal Equilibrium, Thermal Expansion

Answer 2

The hotter system will always transfer heat to the colder one.

Thermal Equilibrium - no heat transfer between systems
Thermal Expansion - increase in temp = expands & decrease in temp = contracts
- can increase/decrease in length/volume

Question 3

Zeroth Law of Thermodynamics

Answer 3

Thermal Equilibrium - no net heat flow between two systems
* If two systems are in thermal equilibrium with the third system then those two are in thermal equilibrium with each other

same temperature = thermal equilibrium

Diathermal walls - allows heat flow
Adiabatic walls - no heat flow

Question 4

First Law of Thermodynamics

Answer 4

This means that heat energy cannot be created or destroyed. It can, however, be transferred from one location to another and converted to and from other forms of energy.

ΔU = Q - W

ΔU - change in internal energy
Q - energy transferred as heat
W - work done on or by the system

Question 5

Second Law of Thermodynamics

Answer 5

Entropy - represents the inevitable partial liss of an engine’s ability to convert heat energy into work.

The total entropy of a system either increases or remains constant in any spontaneous process; it never decreases. Heat transfers energy spontaneously from higher- to lower-temperature objects, but never spontaneously in the reverse direction.

Question 6

Third Law of Thermodynamics

Answer 6

The entropy of a system approaches a constant value as the temperature approaches absolute zero. The entropy of a system at absolute zero is typically zero, and in all cases is determined only by the number of different ground states it has.

Absolute Zero - Temperature decreases (0) = Kinetic Energy decreases (0)