Teacher Site Map 6th Grade Core USOE Science Home Page USOE

Look closely at the globe picture at the right. Have you ever wondered why all globes are tilted? Perhaps someone told you it is because Earth is tilted. But why does that matter? This activity is to help you figure out why Earth is tilted.

Activity:

Materials:

• Flashlight
• A friend

Procedure

1. Work with a partner.
2. One person holds the flashlight directly over the back of the partner’s hand, about 6 inches away for 30 seconds.
3. Now hold the flashlight at a slant on the partner’s other hand, 6 inches away for 30 seconds.
4. Discuss differences in the amount of heat felt.
5. Repeat steps 1-4 with partners trading places.

Study the graphic below and answer the questions that follow.

Graphic courtesy of NASA - designed by a student at Rose Hill Junior High School

Journal Entry

Write down and answer each of the following questions in your science journal.

1. Which “Sun” angle produced the higher temperature?
2. Where on the Earth do the Sun's rays hit the most directly year round?
3. Where on the Earth do the Sun's rays hit at an angle?
4. Why do some areas of the Earth receive direct rays and others angled rays?

Extension Activity

You will need to work closely with a teacher or parent to make sure that you are safe as you use these materials. Most of the materials are probably available in a classroom.

Materials:

• Thermometer
• Black paper

Purpose: You will show that the amount of heat energy absorbed is related to the angle of the light source.

Background: Light is a form of energy that can cause an object to increase in temperature. Have you ever noticed that it is easier to get warmed by the sun's rays when the sun is directly overhead than when it is setting?

Procedure 1:

1. Take a piece of black paper and fold it in half.
2. Place a thermometer inside the folded paper.
3. Place your folded paper directly in front of projector lens in a vertical position as shown in the left photograph.
4. Record the temperature as you begin.
5. Record the temperature again after the light has been shining on the paper for two minutes.
6. Let the paper and thermometer cool to room temperature (about five minutes).
7. Repeat the same procedure holding the paper at a 45-degree angle or greater as shown in the right photograph.
 Vertical Example 45-Degree Example

Procedure 2:

1. Take a piece of black paper large enough to cover the overhead projector.
2. Cut a hole that is about 1/2-inch square in the middle of the paper as shown at the right.
3. Place the projector about one meter (or 36 inches) from the wall. The projector should be facing directly at the wall as shown in Example 1.
4. Measure the area of the light square projected on the wall.
5. Move the projector so it is at an angle of at least 45 degrees to the wall. The projector will be at an angle to the wall as shown in Example 2 below.
6. Move the projector so it is one meter (or 36 inches) from the wall.
7. Measure the area of this square.
8. Optional: Tape black paper on a board. Shine a flashlight directly on the paper. Outline the lighted area with chalk or white crayon.

Angle the flashlight at 45 degrees and outline the lighted area with chalk or a white crayon.

 Example 1 Example 2

Analysis:

1. In Procedure 1, what difference exists between the temperatures after two minutes with the two angles? Which example represents winter in Utah? Why?
2. In Procedure 2, how does the angle of the light affect the size of the area measured? Which example represents winter in Utah? Why?
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Get the plug-ins: , and . (The QuickTime plug-in is needed to play sounds and movies correctly.)

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1. The title of the activity
2. The URL (Internet address)