* Refraction: This bending of light is called refraction. It occurs because light travels at different speeds in different mediums. Light travels slower in Perspex than in air.
* Normal: The normal is an imaginary line drawn perpendicular to the surface of the Perspex at the point where the light ray enters.
* Angle of Incidence and Angle of Refraction: The angle between the incoming light ray and the normal is called the angle of incidence. The angle between the refracted ray and the normal is called the angle of refraction.
Here's how it works:
1. As the light ray enters the Perspex, its speed decreases.
2. The part of the wavefront that enters the Perspex first slows down before the rest of the wavefront.
3. This difference in speed causes the light ray to bend towards the normal.
Key Point: The amount of bending depends on the difference in the speed of light in the two mediums, which is quantified by the refractive index of each material. Perspex has a higher refractive index than air, so light bends more when entering Perspex.
