Grade 2 · Unit 4: Light and dark
Light sources
The Sun, a lamp, a firefly – what gives out light?
We need light to see
Light lets us see the world. Things that give out their own light are light sources.
Light travels very fast – faster than anything else.
Natural light
The Sun is our biggest light source. Lightning, fire and stars give natural light. Fireflies glow at night in the villages.
Without the Sun’s light, plants could not grow and we would have no food.
Artificial light
People make artificial light. Lamps, torches, candles and screens are light sources. At Diwali and weddings people light many little lamps.
Long ago, before electricity, people used oil lamps and candles at night.
Is the Moon a light source?
No! The Moon does not make its own light. It reflects light from the Sun. A mirror, a spoon and a bicycle reflector reflect light too.
The Moon’s shape seems to change each night because we see different amounts of its sunlit side.
What I learnt
- I know that a light source gives out its own light.
- I can name natural and artificial light sources.
- I know that the Moon reflects light from the Sun.