Lab 10: 5 of 7

Supplies

• Small metal can
• Measuring cup
• Thermometer
• Aluminum foil
• Cardboard
• Scissors
• Tape

Procedure

Here comes the sun!  In this experiment, we'll try to harness the sun’s energy. Try to conduct the two parts of this experiment back-to-back, so that the sunlight will be of approximately equal intensity.

A. Absorption

1. Measure the ambient temperature of the water.

First, let’s try a simple method.

• Fill the metal can that you used in the last experiment with the same amount of water that you used last before.
• Add a thermometer to the water,
• Record the starting temperature of the water

2. Measure the temperature of the water after sun exposure.

• Place the can in the sunniest area that you can find for about 30 minutes.
• Record the exact amount of time that you allowed the can to sit in the sun.
• At the end of this time period, record the final temperature of the water

B. Reflectors

1. Begin to construct an apparatus that will more efficiently harness the sun’s energy.

You can begin construction during the 30-minute waiting period.

• Use aluminum foil to reflect the sun’s rays, and attach it to a support of some type.
• For example, you could cover pieces of cardboard with foil and arrange them so as to prepare your “sun catcher”.
  • Feel free to be creative with your design.
• Make careful notes on the design of your apparatus.

2. Start over with a fresh portion of water of the same volume

• Place the metal can containing the water into your “sun catcher” apparatus.
• Be sure to note the initial temperature of the water.
• Allow the apparatus to stay in the sun for the same length of time you recorded on the first pass.
• Record the final temperature of the water.