8th Grade Science
Butler Middle School
Lowell, MA
R. Rogers
Mar 8, 2011
• Thermal Energy
– Total Energy of all the moving molecules in an
object
• Heat
– Thermal Energy moving from a warm object to
a cooler object
• Heat transfers in 3 ways
– Conduction
– Convection
– Radiation
Conduction, Convection, and Radiation
often occur together
• Energy
– Ability to do work or cause change
– Exists in many different forms
• Kinetic Energy
– Energy from motion or movement
• Temperature
– A measure of the average Kinetic Energy of all
the molecules in an object
Thermometer
• Measures Temperature
• Bulb Thermometer
– Based on expansion & contraction
of a liquid in a glass tube
Temperature Scales
K
C
F
Water
WaterBoils
Boils
K & C degrees are same size
F deg are smaller than C deg
Ideal Room Temp, 68° F = 20°
C
Water Freezes
Absolute Zero = Coldest Temp
Experiment
Cold Water in Plastic Pail
Hot Water in Metal Can
Place a thermometer in
pail and in can. Wait for red
line to stop moving.
Record temperature of each,
call this:
“temperature at time 0”
Experiment (continued)
Place metal can with hot water in
plastic pail with cold water
Gently stir water in each
container
Record temperatures of water in
each container every 1 minute
Plot hot water temp and cold water temp vs time
90
80
Hot Water
70
60
Temperature
50
(Deg C)
40
30
Cold Water
20
10
0
1
2
3
4
Time (min)
5
6