Heat Absorption
Marvice Box Lawndale Community Academy
3500 West Douglas Blvd.
Chicago, Illinois 60623
312-542-3635
Objectives:
Grades 8-9
1. Describe how the average kinetic energy of matter is measured.
2. Distinguish between heat and temperature, and calculate a change in a
substance from one state to another.
3. Understand the value of precise data for use in a comparative study.
4. Demonstrate that a colored surface will absorb more heat from a source of
light than a white surface.
5. Explain how instruments detect and measure changes in heat and temperature.
6. Identify the ways in which heat is transferred.
7. To investigate the absorption of heat energy by matter.
8. Analyze data and establish a relationship between factors involved.
Materials Needed:
Thermometers, tin cans, black and white construction paper and cloth,
meterstick, styrofoam cups, charcoal, sand, water, candles, lamp, ice cubes,
graph paper, radiometer.
Recommended Strategy:
Station 1 Discovery Centers - Directions:
A. Place the clip lamp directly above the cups at height 30cm.
B. Design your own table for recording data. Enter the temperature shown on
the thermometer for each material.
C. Turn on the lamp. Record the temperature of the material in each cup after
1, 2, and 5 minutes and report:
1. Construct a graph of the heating data. Represent each material by a
different type of line.
2. Which dry material showed the greatest increase in temperature.
3. Which wet solid showed the greatest increase in temperature.
4. Did the wet charcoal or the dry charcoal show a greater increase in
temperature.
5. Did the wet sand or the dry sand show a greater increase in temperature.
6. How did the increase in the temperature of the water compare to the
increases in the temperature of the solids?
7. When the light was turned off, which material showed the greatest
decrease in temperature.
Station 2 Miniature Greenhouse Discovery Center - Purpose: To investigate
the conversion of light to heat energy - Directions:
A. Arrange a clip lamp so bulb is 50cm from plastic wrap.
B. Design your own table for recording data, enter temperature shown on each
thermometer then turn on the lamp. Record the temperature inside and outside
of the box every 30 seconds for 5 minutes and report:
1. What is the dependent variable in your data? What is the independent
variable?
2. Construct a line graph of the heating data collected in directions above.
Show temperature on the vertical axis and time on the horizontal axis. Use
a solid line for temperature inside, dotted line for temperature outside.
3. Construct a line graph of the cooling data collected in step B. Follow
the procedure in number 2 above.
4. How did the temperature change inside the box compare with those outside?
Station 3 Color and Heat - Directions and Experiment:
1. After lighting the candle, allow a drop of wax to drop on to each sheet of
black and white paper.
2. Place the lighted electric bulb exactly between the two sheets of paper about
3 inches from each. OBSERVATIONS? CONCLUSIONS?
Station 4 Color and Heat Absorption - Experiment:
1. Hold a tin can in a candle flame until it is completely coated with soot.
2. Pour water into both cans until they are full.
3. Record the temperature of the water in each can.
4. Put the two cans of water directly in the sunlight or near a lamp.
5. Take the temperature of the water in each can every five minutes for about a
half-hour. OBSERVATIONS? CONCLUSIONS?
Station 5 A Material's Effect on Radiation - Directions:
1. Place the Black and White pouches flat on a table. Place a thermometer into
each pouch. Place the light source 10cm above the pouches.
2. Turn the light on and record the temperature of each pouch each minute for 6
minutes.
3. Repeat using the black paper. OBSERVATIONS? CONCLUSIONS?
Discussion and Follow-up:
- At Specific intervals during the demonstration, students should be given turns
for taking temperature readings and recording them on a chart.
- Predict what they think the outcome of the demonstration will be.
- After about 6 readings, or whenever a difference in the temperature of 3
substances has been noted, the data collected should be analyzed and a
determination made as to the comparative rate of heating of soil and water.
- Students should be encouraged to report personal experiences at the seashore,
swimming area, wearing light colors in summer, dark colors in winter and
relate the demonstrations to an actual situation.
Summary Statements:
1. The temperature of matter changes when the amount of heat in it changes.
2. Heat energy travels from a warmer to a cooler location.
3. A thermometer is used to measure the temperature of a substance.
4. Black absorbs all colors of light, so more energy is taken in per unit of
time; white reflects all of the colors of light.
5. Much of radiant energy of the sun is changed into heat when it strikes
objects. The black or dark colored materials and objects give off and take
in heat the fastest. The radiant energy absorbed changes into heat.
6. The lighter, white and shiny objects tend to reflect more of the sun's energy.
7. Water, with its high specific heat, will tend to slow any temperature changes
when added to the solids.
8. When exposed to the same source of heat, soil heats at a faster rate than water.
References:
1. Charles R. Barman, John J. Rusch, Myron O. Schneiderwent, Wendy B. Hindia,
Physical Science "Heat Absorption", Pages 260-261, Silver Burdett Company,
1979.
2. Bob Brown Science Circus #1 "The Dark Cloth Test", Pages 48, 51, Fleet Press
Corp., New York, 1980.
3. Dorothea Allen, "Science Demonstrations for Elementary Classroom", Parker
Publishing Company, West Nyack, New York 10995, 1988.
Return to Physics Index