Physics: Heat Transfer and Thermodynamics Notes (copy) (copy) (copy) (copy) (copy) (copy) (copy) (copy) (copy) (copy) (copy) (copy)

Celsius Scale

Based on where water freezes and where water boils.

Kelvin Scale

Based on the movement of particles.

Absolute Zero

Occurs at 0 K, where all particles stop moving.

0 K

Equates to -273.15 degrees Celsius.

Thermal Expansion

Causes objects to expand when heated and contract when cooled.

Kinetic Energy

Energy associated with the movement of molecules.

Heat Flow in Substances

Energy travels from high energy to low energy.

Conduction

Energy transferred through direct contact.

Convection

Energy transferred through the mixing of fluids.

Radiation

Energy transferred by the emission of electromagnetic waves.

Specific Heat

The specific amount of energy needed to raise the temperature of a certain material.

Heat Formula

Q=mcΔT, where Q is heat (joules), m is mass (kg), c is specific heat, and ΔT is change in temperature.

Law of Conservation

The total amount of energy always remains the same.

Conductors

Materials that conduct heat well (e.g., metals, water).

Insulators

Materials that do not conduct heat well (e.g., insulation, foam, air).

Entropy

Measure of disorder in a system.

First Law of Thermodynamics

If the total increase in thermal energy of a system equals the sum of the heat added to it, energy is conserved.

Second Law of Thermodynamics

Entropy of the universe is always maintained or increasing.

Third Law of Thermodynamics

Entropy decreases as temperature decreases.

Kinetic Energy vs Potential Energy

Kinetic energy is associated with movement; potential energy is stored energy.