Here's a breakdown:
* Refraction: The change in direction of a wave as it passes from one medium to another. This occurs because the speed of the wave changes as it moves from one medium to another.
* Angle: The angle at which the wave strikes the boundary between the two media is called the angle of incidence. The angle at which the wave bends as it enters the second medium is called the angle of refraction.
* Medium: A medium is a substance that a wave can travel through. For example, air, water, glass, and vacuum are all media.
Why does refraction occur?
The speed of a wave depends on the properties of the medium it travels through. When a wave enters a medium with a different density or elasticity, its speed changes. This change in speed causes the wave to bend.
Examples of refraction:
* A straw in a glass of water: The straw appears bent at the point where it enters the water because light travels more slowly in water than in air.
* A rainbow: Rainbows are formed when sunlight is refracted by water droplets in the air.
* Lenses: Lenses use refraction to focus light, which is how they are used in eyeglasses, cameras, and telescopes.
Let me know if you'd like more information about any of these concepts.
