* Refraction: This is the phenomenon where light bends as it passes from one medium to another. The bending occurs because light travels at different speeds in different media.
* Normal: The normal is an imaginary line perpendicular to the surface at the point where the light ray hits the surface.
* Dense Medium: A medium with a higher refractive index, meaning light travels slower in it. Examples include water, glass, and diamond.
* Less Dense Medium: A medium with a lower refractive index, meaning light travels faster in it. Examples include air and vacuum.
Why does the light bend away from the normal?
* When light enters a less dense medium, it speeds up.
* This speed change causes the direction of the light ray to change.
* Since the light is speeding up, it bends away from the normal.
Example:
Think of a straw in a glass of water. The straw appears bent at the water's surface because light travels slower in water than in air. When the light ray from the straw enters the air, it bends away from the normal, making the straw appear to be bent.
Important Note:
The angle of refraction depends on the angle of incidence (the angle at which the light ray hits the surface) and the refractive indices of the two media. This is described by Snell's Law:
n1 * sin(θ1) = n2 * sin(θ2)
where:
* n1 and n2 are the refractive indices of the two media
* θ1 is the angle of incidence
* θ2 is the angle of refraction
In summary: When a ray of light travels from a more dense medium into a less dense medium, it bends away from the normal due to the change in speed. This phenomenon is called refraction and is described by Snell's Law.
