# How does color affect heat energy absorbed from light?

How does color affect heat energy absorbed from light?

### Required Materials

• Two equally calibrated thermometers
• Heat lamp (or a high wattage bulb)
• One sheet of white paper and one sheet of black paper of the same thickness.
• Paper and pencil

### Procedure

1. Prop the thermometers in an upright position about 20 cm (8 in.) parts, facing in the same direction.
2. Record the temperatures of both thermometers.
3. Place the sheet of white paper front of one thermometer and the black paper in front of the other.
4. Shine the heat lamp at the sheets of paper in such a way that it faces both equally. It should be about 40-50 cm (16-20 in.) away from the papers.
5. After the heat lamp has shone on the papers for about two minutes, check and record the temperatures of the two thermometers again.
6. Repeat for two more minutes and again record the temperatures.
7. Compare the changes in the first and last temperature readings of the two thermometers.
8. What can you say about the effect of color in this activity?

### Other Ideas.

in the above activity you compared the heat absorption from white paper and black paper. Find several different colors paper. Use only paper that is the same except for color. Construction paper will work well. From what you have already learned, predict which colors will absorb the most heat from the light bulb and which will reflect the most heat. Arrange the papers in order, according to your predictions. Design an investigation to find out if your predictions are accurate.

### Some questions.

Were you right? Why is it important that you don’t use construction paper for some colors, typing paper for some colors, and art paper for still other colors?

That raises another interesting question –does one type of paper absorb more heat than another? Now, to test that question, what will you do about color?