Refraction occurs when a wave…

Refraction occurs when a wave changes its direction as it passes from one medium to another. This change in direction is due to a change in the wave's speed. Here are the steps to understand this process:

1. Incident Wave: A wave approaches the boundary between two different media. For example, light traveling from air into water.

2. Change in Speed: When the wave enters the new medium, its speed changes. The speed of the wave depends on the properties of the medium. For instance, light travels slower in water than in air.

3. Change in Direction: Due to the change in speed, the wave changes its direction. This bending of the wave is called refraction. The amount of bending depends on the angle at which the wave enters the new medium and the difference in speed between the two media.

4. Snell's Law: The relationship between the angles and the speeds of the wave in the two media is given by Snell's Law, which states: $n_1 \sin(\theta_1) = n_2 \sin(\theta_2)$ where $n_1$ and $n_2$ are the refractive indices of the first and second media, and $\theta_1$ and $\theta_2$ are the angles of incidence and refraction, respectively.

5. Refractive Index: The refractive index of a medium is a measure of how much the speed of the wave is reduced inside the medium. It is defined as: $n = \frac{c}{v}$ where $c$ is the speed of light in a vacuum and $v$ is the speed of light in the medium.

By following these steps, you can understand how and why refraction occurs when a wave passes from one medium to another.