slms 7 th grade science energy effects

SLMS 7th Grade Science

Energy Effects

Lesson 7How the angle of the Earth

is related to the heatingby the sun

Only a tiny amount of light energy from the sun is transformed to heat energy on Earth.O What we think about….. 1. How does this statement relate to the distance between the sun and Earth? 2. How does it relate to difference in size between the sun and Earth? 3. Draw a model of sun in relation to the Earth. (Distance and size) 4. How is it related to the shape and axis/tilt of the Earth?

PART 1

DemonstrationsSun, Earth, and Moon

Relative Size of Earth to Sun

Questions

How much of the sun’s light energy reaches the Earth?

How does the relative size of eachaffect the amount of energy that reaches the Earth?

ActivityO PROCEDURE: 1. Shine the flashlight on the graph paper at 90, 45, and 20 degree angles. Outline the lighted area. 2. Count the number of squares lighted at each angle. 3. Make a data chart to record your data.

Lakers are Over-Achievers so…..

Calculate the surface area of light at each angle.

Pi = 3.14

Questions

1. How do your observations explain how the sun warms the Earth?2. What happens to the light intensity as the angle is increased? Explain why?3. How does the light intensity affect how light is absorbed and converted to heat on Earth?4. How could we alter the activity to answer question three (3)?5. Which angle would result in the most heat? Why?

Let’s Find Out

Part 2Questions

Reflective properties of matter on Earth and atmosphere

1. What minerals are found on Earth?2. How do Earth materials reflect, absorb,

transmit?3. How does the atmosphere interact with solar

light?4. How does it relate to the amount of sunlight

absorbed by the Earth?5. What would happen without the ozone layer

in the atmosphere?

Wrap Up /Journal EntryOnly a tiny amount of light energy from the sun is

transformed to heat energy on Earth.

O The sun radiates light in all directions and travels in a straight path outward from the sun. The Earth is so far away that it is in the path of an extremely small amount of the sun’s total light and heat energy.

O The heating of the Earth is related to the angle of the sun in the sky and the Earth’s tilt. Only a small part of the Earth’s surface is in the path of direct sunlight where more light can be absorbed.

O Some material on Earth and in the atmosphere absorbs sunlight and converts it to heat. Some light is reflected and not converted to heat.