What you need:
- A torch
- Water
- A glass
- A small mirror
- A plain wall
- A dark room
What to do:
1. Go into a darkened room. Place a glass of water on a table in the room, opposite a blank wall.
2. Place the mirror into the water, at an angle, facing the wall.
3. Shine the torch on the mirror through the water and the glass.
What happens:
A rainbow appears on the wall opposite the mirror. If you don’t see it, adjust the angle of the mirror and try again.
Why?
Light bends when it travels through different materials or media. This bending of light is called ‘refraction”. When the light beam from your torch passes through the glass and the water, it bends. But light isn’t just one colour. White light is a combination of seven colours (violet, indigo, blue, green, yellow, orange and red). So when the light bends, all its colours also bend. But each colour bends at a different angle because each colour beam travels at a different speed in glass or in water.
This split beam of light hits the mirror which reflects it back. That’s how you get to see the different colours of the rainbow on the opposite wall!
Picture Credit : Google
