THERMAL ENERGY TRANSFER

THERMAL ENERGY Thermal energy is the total amount of energy in an object’s moving molecules. Heat is the flow of thermal energy from a warmer object to a cooler object

Definition of Temperature The measure of the average motion of all the molecules and or atoms in an object. Freezing point- Celsius 0, Fahrenheit 32, Kelvin 273 Boiling point- Celsius 100, Fahrenheit 212, Kelvin 373

Specific Heat Specific heat is the relationship between heat and temperature change. OR How much energy does it take to get this thing hot? Water has very high specific heat Metals have low specific heat

Objects and Energy Flow Conductors carry energy Examples: metals Insulators slow down energy flow Examples: plastic, air, styrofoam

Types of Heat Transfer Conduction: transfer of thermal energy by direct contact of a heat source. Example: pan on a stove top, feet on cold floor, hands on hot drink

Convection: thermal energy will cause molecules to heat up and rise until the molecules cool and fall back down. Example: wind, ocean currents, steam, magma under the earth’s crust, rice grains rise and fall in boiling water.

Radiation: thermal energy moving through space and does not require matter. Example: Warmth from a fire, light from the sun, electromagnetic spectrum

Heat Transfer with a Fireplace Conduction- Fast-moving particles in the fire transfer heat as they collide with slow-moving particles in the metal tools. Convection- When the air around the fire is heated, it becomes less dense than the cooler air nearby and rises. Radiation- The fire transforms chemical energy in the wood to electromagnetic energy, which radiates throughout the room.

REMEMBER Energy always travels from an area of HIGH energy to LOW energy! Heat flows from hot to cold objects.