Refraction and diffraction

Question 1

Refraction

Answer 1

When a waves crosses a boundary between two materials it changes speed. If the waves hits the boundary at angle, the waves become refracted.

Question 2

How does refraction work?

Answer 2

The waves bends towards the normal if it slows down. It bends away from the normal if it speeds up. The wavelength changes, but the frequency stays the same.

Question 3

Angle of incidence

Answer 3

The angle between the incident ray and the normal.

Question 4

Diffraction

Answer 4

Is the spreading of waves when they pass trough a gap. Waves spread out without changing their speed, wavelength or their frequency. The narrower the gap is, the more the waves spread.