The Sun:Our Primary Source of Heat

Jennifer Currier & Cassie BurnettGLCE: E.ES.01.11 Identify the sun as the

most important source of heat which warms the land, air, and water of the Earth.

Engage: Reading a short story called: The Tale Of Wendy Wizard

Explore:

Explore:Materials:•Cardboard pizza box (the kind delivered pizza comes in)

•Box knife or scissors•Aluminum foil•Clear tape/ Electric tape or glue•Plastic wrap (a heavy-duty or freezer zip lock bag will also work)

•Black construction paper•Metal pan•Food to cook

Lets Get Started!!!!!

Explain:What's happening?

The heat from the sun is trapped inside of your pizza box solar oven, and it starts getting very hot. Ovens like this one are called collector boxes, because they collect the sunlight inside. As it sits out in the sun, your oven eventually heats up enough to melt cheese, or cook a hot dog!

How does it happen? Rays of light are coming to the earth at an angle. The foil reflects the ray, and bounces it directly into the opening of the box. Once it has gone through the plastic wrap, it heats up the air that is trapped inside. The black paper absorbs the heat at the bottom of the oven

Your solar oven will reach about 200° F on a sunny day, and will take longer to heat things than a conventional oven. Although this method will take longer, it is very easy to use, and it is safe to leave alone while the energy from the sun cooks your food. If you do not want to wait long to have a solar-cooked dish, try heating up something that has already been cooked, like leftovers, or a can of soup. Putting solid food in a glass dish and liquids in a heavy plastic zip lock bag works well. You can also pre-heat your oven by setting it in direct sun for up to an hour.

Solar Energy Our earth gets most of its energy from the sun. We call this energy solar energy. Solar energy travels from the sun to the earth in rays. Some are light rays that we can see. Some are rays we can't see, like x-rays. Energy in rays is called radiant energy. The sun is a giant ball of gas. It sends out huge rays of energy every day. Most of the rays go off into space. Only a small part reaches the earth. When the rays reach the earth, some bounce off clouds back into space--the rays are reflected. The earth absorbs most of the solar energy and turns it into heat. This heat warms the earth and the air around it--the atmosphere. Without the sun, we couldn't live on the earth-it would be too cold.

Explain:

WE USE SOLAR ENERGY TO SEE AND GROW THINGS We use solar energy in many ways. During the day, we use sunlight to see what we are doing and where we are going. Plants

Plants use the light from the sun to grow. Plants absorb (take in) the solar energy and use it to grow. -The energy stored in plants feeds every living thing on the earth. When we eat plants and food made from plants, we store the energy in our bodies. We use the energy to grow and move. We use it to pump our blood, think, see, hear, taste, smell and feel. We use energy for everything we do.

WE CAN USE ENERGY FROM THE SUN FOR HEAT We also use the energy stored in plants to make heat. We burn wood in campfires and fireplaces. Early humans burned wood to provide light, cook food, scare away wild animals, and keep warm.

Solar energy turns into heat when it hits objects. That's why we feel warmer in the sun than in the shade. The light from the sun turns into heat when it hits our clothes or our skin. We use the sun's energy to cook food and dry our clothes.

THE SUN MAKES THE WIND Solar energy makes the winds that blow over the earth. The sun shines down on the land and water. The land heats up faster than the water. The air over the land gets warm. The warm air rises. The cooler air over the water moves in where the warm air was. This moving air is wind.

THE SUN'S ENERGY IS IN MANY THINGS

Solar energy powers the water cycle. The water cycle is how water moves from clouds to the Earth and back again. The sun heats water on the earth. The water evaporates-it turns into water vapor and rises into the air to form clouds. The water falls from the clouds as precipitation--rain, sleet, hail or snow.

Divide the class into two groups

Give each group a “what if” question to think about.

1. What if the sun never set and the sun stayed in the sky heating the earth with no night?

2. What if the sun never rose and there was only darkness on the earth with no sun?

Elaborate:

Both groups will get time to discuss their thoughts about a good answer to each of the questions.

Each student will participate with their own ideas and as a group come up with the answer the whole group decides is best.

Pick a representative from each group to share the answer to the “what if” question with the class.

Evaluate:

Resources:

http://www1.eere.energy.gov/education/pdfs/solar_energyfromsunguidestudent.pdf