1. Heat and Heat Technology
Section 2 – What is Heat? pp

2. TERMS TO LEARN
Heat – the transfer of energy between objects that are different temperatures
Thermal energy – the total energy of the particles that make up a substance
Conduction – the transfer of thermal energy from one substance to another through direct contact (touching)

3. TERMS TO LEARN
Convection – the transfer of thermal energy by the movement of a liquid or gas
Radiation – the transfer of energy through matter or space as electromagnetic waves, such as visible light and infrared waves.

4. METHODS OF HEAT TRANSFER
Conduction
Convection
Radiation

5. CONDUCTION How it works
When substances come in contact with each other, particles collide (hit each other)
And thermal energy is transferred from the higher temperature substance to the lower temperature substance.

6. CONDUCTORS VS. INSULATORS
Conductors are substances that conduct thermal energy very well
Examples include: metals
Insulators are substances that do not conduct thermal energy very well.
Examples include: nonmetals, wood, styrofoam, plastic

7. CONVECTION How it works: See Figure 5 on p. 283 of text.
Water in the bottom of the pot gets hot.
The hot water gets less dense.
The warm water rises through the denser, cooler water above it.
The denser, cooler water on top of the pot sinks to the bottom of the pot.

8. CONVECTION
The circular motion of liquids or gases due to differences in density because of temperature is called a convection current.

9. RADIATION How it works: See Figure 6 on p. 284 of text.
Coils of heater warm a room by radiating visible light and infrared waves.
Radiation and the Greenhouse Effect: See Figure 7 on p. 284 of text.
Complete “Feel The Heat” WS.