* Angle of Incidence: This is the angle between the incoming light ray (incident ray) and the normal line (a perpendicular line drawn to the surface at the point of incidence).
* Angle of Refraction: This is the angle between the refracted ray (the light ray that passes through the surface) and the normal line.
Key Relationship: The relationship between the angle of incidence and the angle of refraction is governed by Snell's Law:
* n₁sinθ₁ = n₂sinθ₂
Where:
* n₁ and n₂ are the refractive indices of the two mediums (e.g., air and water).
* θ₁ is the angle of incidence.
* θ₂ is the angle of refraction.
Why they differ:
* Change in Medium: When light passes from one medium to another (like air to water), its speed changes. This change in speed causes the light ray to bend, resulting in the angle of refraction being different from the angle of incidence.
* Refractive Index: The amount of bending depends on the refractive indices of the two mediums. The greater the difference in refractive indices, the greater the difference between the angles of incidence and refraction.
In Summary:
* Angle of incidence describes the direction of the incoming light ray.
* Angle of refraction describes the direction of the light ray after it has passed through the interface between two mediums.
* They are related by Snell's Law, and they are generally different angles.
