Seasons: Torch and board
Classroom Activity for 11-14
In this activity students use a lamp and piece of paper to show how the light from the Sun spreads out more when it strikes the Earth at an angle.
Apparatus and Materials
Each student will need
- Large piece of card
- Board to which card can be fixed
- Lamp with cardboard cylinder
- Two different coloured marker pens
- Put a cardboard cylinder around the end of the lamp to provides a rougly circular area of light.
- Draw a line around the area where the light falls when the card is perpendicular to the light source,
- Repaet for when the board is at an angle.
The demonstration shows that when light hits a surface at an angle it is spread out over a greater area than if it strikes the surface perpendicularly. Any energy transfer is therefore spread over a greater area.
In place of the card, a photocopied map could be used to make the demonstration look more like a part of the Earth's surface.