light into heat

Solar Houses- Does Light convert to Heat?

Instructional Objectives- Students will learn key scienctific process skills in order to answer a fundamental question about how solar energy can be converted. Building an experimental model, following sequential data gathering steps, analyzing data, and writing conclusions will all be taught and used.
Time Required-Two 45 minute periods.
Advanced Preparation and prerequisite knowledge/skills-Use either the supplied template and instructions, or pre-order the GEMS unit. Have team template sheets and data recording sheets either per team, or one per student (depending on your accountability desires)
Materials- card stock & model template, transparency strips (for window) thermometers.

Procedures:

1. Day 1 is for construction, and as in all of these activities, bringing in the vocabulary of the studies into the discussions before, during, and after working.
-Introduce the question- ¿Can Solar energy (light) be converted into heat? (again, the idea is that we can USE solar energy if we understand how to interact with it)
- Explain the basic methodology of experimentation:
1. start with a question or problem.
2. hypothesize, or speak out an idea that seems to be true based on current experience... AND
which can be tested with materials and skills available to you (the hypothesis is tied to design)
3. Set up an experiment which allows you to compare two "variables"..... in this case:
Does light coming in a window heat a room more than if the light is kept out? (or similar language)
4. Design procedures that allow you to observe and record how the two different models react
to the test. Measurement is the 6th sense, to go with our other 5 senses for observing.
5. Run the experiment, carefully recording all data in an organized way (data table)
6. Analyze the data (discuss it, picture it by graphing and drawing)
7. Use the data in justifying your conclusions/answer for the question- Does Light become Heat?

2. Build the passive solar houses- Make sure they think through the idea that a well sealed (taped) room should hold in any energy that comes in= Insulation. (*if you are going to teach about HEAT then either before, during, or after this exploration you can work with vocabulary of 3 types of heat- Radiation, Conduction, and Convection... for the purposes of this lesson Radiation is when the sun's heat moves through the air as light, without moving the air (convection is an actual moving of the heated air/water/lava)
3.Test thermometers-If there is time (probably won't be) have the students test handling the thermometers carefully, and reading the correct markings. (many thermometers are both degrees fahrenheit & Celsius... need to choose one scale and all use it for all of the readings.)

Day 2: Record temperature changes on data sheet
1. take cardboard or notebook etc. to set solar houses on so that that aren't absorbing heat from different ground surfaces.... the one variable is "window open or closed".PREDETERMINE which houses are open, and which closed.
2. Help them understand how to: Angle window toward sun, but with thermometer bulb not being directly hit by light, AND how to seat themselves so that they aren't blocking light from the houses during the procedures.
3. Go over the "every minute read & record" process..... it's good and fun to do countdowns for each " 10,9....... record!". JUST put the number in the data box..... don't worry about placing graph points yet.
4. Go inside, graph each, and then post "temperature change" for each team on the board, in a simple data table. Graph "open" "closed" in two different lines or bars to get comparative class data.
5. ** You can have each team go through the "analyze & write conclusions" steps, or more likely for this stage of their skills, do it as a guided process using their data, and then the whole class data set.
6. Write a several sentence conclusion that uses the form:
"We were trying to figure out if light changes into heat so maybe we can heat our houses that way. We put model houses in the sun, 1/2 with a window open, and 1/2 with it closed. All of them were sealed up well, so that any energy going in would stay there. We found out that the open windows changed temperature from ___ to ____ in 10 minutes. The closed windows changed from _____ to _______. This tells us that__________. As a follow-up experiment we want to (try different colors, different materials, different size/shape, etc)"