Thermal Energy and Heat

matter

contains particles and kinetic energy (KE)

temperature

average kinetic energy (KE)

Thermal energy

Total Kinetic Energy (KE)

Amount of thermal energy depends on 3 things

1. temperature

2. mass (amount of particles)

3. density (particle arrangement)

conductivity of thermal energy based on state of matter

gas = terrible

liquid = ok

solid = best

HEAT and transfer of thermal energy is affected by these 5 factors

1. Temperature difference

2. Conductivity of material

3. State of material

4. Density (mass per volume)

5. Distance between particles/surfaces/objects (how close they are to one another to transfer energy)

heat

transfer of thermal energy by conduction, convection or radiation

equilibrium

state of balancewhere thermal energy is evenly distributed among objects, resulting in no net heat transfer.

This state is reached when the average kinetic energy of the molecules in both systems is equal. When objects reach thermal equilibrium, they have the same temperature, and the flow of heat stops.

conduction

transfer of thermal energy through direct contact

most efficient

TOUCHING

convection

transfer of thermal energy by the movement of fluids (liquids or gases) due to density differences caused by temperature variations.

circulation

radiation

transfer of thermal energy through electromagnetic waves

does not need matter to transfer the energy

examples of conduction

touching a hot stove and getting burned

melting an ice cube when held in hands

heat from a stovetop transferring into a metal pot

examples of convection

boiling water in a pot

warm air rising in a room

ocean currents circulating warm and cold water

Hot air balloon

examples of radiation

the warmth you feel from the sun

the heat from a fire

the radiation emitted by a microwave oven

temerature gradient

one place being hotter than another and the thermal energy will move towards the cooler object (from one hotter area to a cooler area)