LAB #7 – Heating Earth’s Surface

LAB #7 – Heating Earth’s Surface

Sometimes, a plunge in a pool or lake on a hot summer day feels cool and refreshing. Why does the beach sand get so hot when the water remains cool? A few hours later, the water feels warmer than the land does.

Problem

What is the effect of radiant energy from a light bulb on the temperature of a beaker filled with "land" and a beaker filled with "sea"?

Hypothesis

If we add radiant energy from a light bulb to beakers filled with "land" and "sea" then the temperatures of the beakers will................
and this is because............?

Materials

Soil
Metric ruler
Water
Containers for soil and water 
Overhead light 
Thermometers 

Stopwatch

Procedure 

1.             Add 500 ml of water to one of the boxes and 500 ml of soil to the other box.

2.             Use a thermometer to find the temperature of the water and soil in each container. Record your data in the Results section.

3.             Place the containers side by side underneath the overhead light. Be sure both containers receive the same amount of light.

4.             Measure the temperature of the water in each container at 1-minute intervals for 10 minutes. Record your data in the Results.

5.             After you record your 10 minute reading, turn off the light and take your initial reading with the light off.

6.             Measure the temperature of the water and soil in each container at 1-minute intervals for 10 minutes. Record your data in the Results.

Results

	Temperature With Light On (°C)			Temperature With Light Off (°C)
Time (min)	Soil	Water	Time (min)	Soil	Water
0			0
1			1
2			2
3			3
4			4
5			5
6			6
7			7
8			8
9			9
10			10

Analysis

1.         Graph the data from the table using a line graph in degrees Celsius. Use one colored pencil to show data for the water container and a different one to show data for the soil container with the light on.  Make a second graph with the light off. X-Axis: Time (min.), and Y-Axis: Temperature (°C). Draw lines to connect the temperature for each container.

2.         Calculate the total change in temperature for each material.  Do this by using the following formula: Total Change = Final Temperature - Initial Temperature or 10 min. - 0 min.

3.         Which material had the greater increase in temperature?  Which material cooled faster?  Why do you think this is?

4.         Infer from your graphs which cooled faster—the water or the soil.  How could you prove this?

5. What was your independent variable?  What was your dependent variable?  What are two variables that should remain constant?

6. Relate: What is this modeling in the real world? (Hint: remember the video clips)

7a. Draw a picture of the lab setup with the light on.  Label the following: lithosphere (land), hydrosphere (water), sun (light), convection arrow/heating up, convection arrow/cooling down, sea breeze.
7b. Draw a picture of the lab setup with the light off.  Label the following: lithosphere (land), hydrosphere (water), convection arrow/heating up, convection arrow/cooling down, land breeze.

Conclusion

What was your problem?

Restate your hypothesis.  Was it right? wrong?  why or why not?

What did you learn in this lab?

What did you like about this lab?

What were some challenges you had to deal with?

What could you do next with this problem?  What other tests could you perform?

Write down any other additional thoughts, observations, inferences, etc.