1. The Speed of Light Changes:
* Light travels at its fastest in a vacuum (approximately 299,792,458 meters per second).
* When light enters a denser medium like water or glass, it encounters more particles, which slows it down.
2. Snell's Law:
* This law describes the relationship between the angle of incidence (angle at which light hits the surface), the angle of refraction (angle at which light bends after entering the medium), and the refractive indices of the two media.
* The refractive index of a medium is a measure of how much light slows down when it enters that medium. A higher refractive index means a slower speed of light.
3. Bending Towards the Normal:
* When light travels from a less dense medium (like air) to a denser medium (like water), it slows down.
* To conserve the direction of propagation of energy, the light ray bends toward the normal line (an imaginary line perpendicular to the surface).
* The amount of bending depends on the difference in the refractive indices of the two media.
Analogy:
Imagine a car driving on a smooth road (less dense medium) and then entering a muddy field (denser medium). The car will slow down in the field. If the car enters the field at an angle, it will need to change its direction slightly to maintain the overall direction of travel. This change in direction is similar to the bending of light.
In summary, the bending of light toward the normal when it enters a denser medium is a consequence of the change in the speed of light and the principle of conservation of energy.
