Heat Energy

Students should be able to...

Explain how heat transfers from warm objects to cool objects until they are all at the same temperature.
Know how warmer objects can warm cooler objects by contact (conduction).
Know that objects can be warmed at a distance from radiation, (transfer of heat by electromagnetic waves) and the sun is the main source of electromagnetic energy on Earth.
Know that objects can be warmed from a distance by convection (the movement of thermal energy through gases or liquids). Convection moves thermal energy around Earth through the atmosphere and oceans, influencing our weather.
Know that heating and cooling can cause change in the properties of materials (water can be frozen into ice or heated to make steam).
Investigate what happens to molecules as they are heated and cooled.
Know that not all materials respond in the same way to being heated and cooled (explore more materials than just water).
Know some materials conduct heat better than other materials.
Know how poor conductors can reduce heat loss (insulators).
Understand the difference between heat and temperature.

Resources

Vocabulary

thermal energy: The motion of atoms and molecules that creates a change in temperature.

temperature: the measure of how warm something is

transfer: the movement of something from one place to another. Heat always moves from something WARMER to something COOLER.

conduction: the passing of heat through a material while the material itself stays in place. Two things must be touching each other for conduction to occur!

For example: a pot on a stove, touching hot monkey bars

convection: the flow of heat through a liquid or a gas, causing hot parts to rise and cooler parts to sink.

For example: Warm air rising, the top of a pool being warmer than the bottom

convection currents: warm liquids rising or gases rising

For example: hot air balloon, water boiling

radiation: The transfer of heat through electromagnetic rays

For example: sun warming the outside of your car, roasting marshmallows by a fire

Insulator: a material that reduces or prevents heat from passing through. The best insulators are wood and plastic.

Conductor: a material that allows heat to pass through it while the material itself stays in place. The best conductors are metals.

electromagnetic waves: a wave that travels at the speed of light through space due to radiation.

*Objects expand as they are heated because the molecules get EXCITED! Objects contract as they are cooled. For example, train tracks expand during the summer months when it is warmer, sidewalks have cracks in them to allow for expansion when its hot