Waves: Refraction of waves.

Question 1

What happens when waves move from one medium to another?

Answer 1

• Waves can change speed or direction.
• Waves slow down: Bends towards the normal line.
• waves speed up: Bend away from the normal line.

Question 2

What is the exception to this?

Answer 2

• If the waves enter or leave the medium at right angles to the surface, (Along the normal) they do not change direction.

Question 3

What is a wave front?

Answer 3

• Imagery line that connects all the same points in a set of waves.
• Makes it easier to visualise lots of waves moving together.

Question 4

How do wave fronts show refraction?

Answer 4

1) When waves come into contact with a different medium, the waves begin to slow down.
- Causes the waves to become closer and the wavelength gets smaller.
- Causes waves to change direction towards the normal (refracts).
- When waves speed up they change direction away from the normal.

Wave fronts approaching along the normal line:

• Waves slow down when they approach the different medium.
• Whole wave front slows down at the same time.
• Waves do not change direction.