1. Chapter 10 - Heat and Heat Technology Section 1 – Temperature pp. 273 - 279

2. TERMS TO LEARN Temperature –a measure of the average kinetic energy of the particles of an object Thermal expansion – the increase in volume of a substance due to an increase in temperature Absolute zero – the lowest temperature on the Kelvin scale

3. TEMPERATURE Decide whether each of the following temperature is hot or cold: 60°F0° C 60° C100° F 37° F70° F 37° C

4. TEMPERATURE Temperature is a specific measure of how hot or cold something is. Temperature depends on the Kinetic Energy (K.E.) of the particles. The faster the particles move, the more kinetic energy they have. The slower the particles move, the less kinetic energy they have.

5. TEMPERATURE Temperature is an average measure. The temperature of a substance is not determined by how much of the substance you have.

6. MEASURING TEMPERATURE A thermometer is used to measure temperature because of thermal expansion. As a substance gets hotter, its particles move faster and spread out.

7. TEMPERATURE SCALES There are three temperature scales. They are: Kelvin Celsius Fahrenheit

8. TEMPERATURE CONVERSIONS To Convert From:Use this equation: ° C → ° F° F = (9/5 × ° C) + 32 ° F → ° C° C = 5/9 (° F – 32) ° C → K K = ° C + 273 K → ° C ° C = K - 273

9. TEMPERATURE CONVERSIONS Complete the Math Practice on p. 277 of text

10. MORE ABOUT THERMAL EXPANSION Thermal expansion joints are built into bridges so that when it gets hot the bridge does not buckle due to thermal expansion. Cars make a thuh- thunk noise when they go over these on a bridge.

11. HOW A THERMOSTAT WORKS Thermostats work by thermal expansion. As the temperature drops below the desired level, the bimetallic strip coils up and the glass tube tilts. A drop of mercury closes an electric circuit that turns the heat on.

12. HOW A THERMOSTAT WORKS As the room temperature rises above the desired level, the bimetallic strip uncoils. The drop of mercury rolls back into the tube. This opens the circuit and the heater turns off.