Interactions of Waves Notes

The four basic wave interactions are reflection, refraction, diffraction, and interference.

1. Reflection

Reflection is the bouncing back of a wave after it strikes a boundary that does not absorb all the wave’s energy

*The law of reflection states that the angle of incidence is equal to the angle of reflection.

2. Refraction

Refraction is the bending of waves due to a change in speed

*occurs because waves move at different speeds in different mediums*the bigger the change in speed the more the wave will bend

Click on the Fish to watch a Refraction Video Clip

3. Diffraction

Diffraction is the bending of waves around the edge of an obstacle

Watch a BrainPop on Refraction & Diffraction

4. Interference

Interference is when two or more waves arrive at the same place at the same time

*Waves can combine in two different ways.

A. Constructive Interference - waves combine to make a wave with a larger amplitude. After the waves pass through each other, they continue on as if they had never met

B. Destructive Interference – waves combine to make a wave with a smaller amplitude