1. Warm up: copy this summary of yesterday’s lesson in your notes Thermal Energy vs. Temperature vs. Heat
Thermal Energy
Temperature
Heat
the total amount of potential and kinetic energy
a measure the average kinetic energy in object
the movement or transfer of energy between objects that are at different temperatures
Units : joules
Units: Fahrenheit, Celsius, or Kelvin
Units: joules or calories
Always flows from warm objects to cool objects

2. Specific Heat Different substances heat up more easily than others.
Specific heat: The amount of thermal energy needed to raise the temperature of 1kilogram of a material 1°C
Different substances heat up more easily than others.
Objects with high specific heat value require more thermal energy to raise temperature
Objects with low specific heat value less thermal energy to raise temperature

3. Table of Specific Heat Values Which substance is most difficult to raise temperature?
(cal/g0C)
(J/kg0C)
Air
0.25
1,046
Aluminum
0.22
899
Copper
0.09
387
Glass
0.20
837
Ice (-200C to 00C)
0.50
2,090
Iron
0.11
448
Mercury
0.03
138
Ocean Water
0.93
3,894
Water
1.00
4,187
Wood
0.42
1760

4. Calculating changes in thermal energy
Change in thermal energy=(Mass)(Temperature change)(Specfic Heat)
Formula:
Q=(m)(ΔT)(C)
What does Q stand for?
What does ΔT stand for?
What does C stand for?

5. Copy down this Practice problem
The air in a room has a mass of 50 kg and a specific heat of 1,000J/(Kg°C). What is the change in thermal energy of the room when it warms from 20°C to 30°C?

6. Calculating thermal energy changes
Assignement. Complete practice problems on worksheet.