Wave Interaction: Reflection and Refraction

Reflection

• Law of Reflection: When a wave hits a surface, the angle it comes in at ($\theta_i$) is the same as the angle it bounces off ($\theta_r$). $\theta_i = \theta_r$

• Simple Concept: Think of it like a ball bouncing off a wall. The wave keeps its energy but changes direction.

Refraction

• Snell's Law: This is all about how waves bend when they go from one material to another. $n_1 \sin(\theta_1) = n_2 \sin(\theta_2)$

  • Here, $n$ is called the refractive index, which tells us how much the wave will bend.

• Example: When light moves from air (where $n$ is about 1.00) into water (where $n$ is about 1.33), it slows down and changes direction.

Summary

• Why It Matters: Reflection helps us understand how mirrors work, while refraction is important for lenses and taking clear pictures.

Learning about these ideas helps us predict how waves behave in different materials.