Refraction and Diffraction

Question 1

When do waves diffract? What does that mean?

Answer 1

When they pass through a gap or pass an obstacle .

Diffract = spread out

Question 2

What does the amount of diffraction depend on?

Answer 2

The size of the gap relative to the wavelength of the wave.

Question 3

Diffraction: Gap much wider than wavelength =

Answer 3

little diffraction

Question 4

Diffraction: Gap a bit wider than wavelength =

Answer 4

Diffraction only at edges

Question 5

Diffraction: Gap the same as wavelength =

Answer 5

Maximum diffraction

Question 6

Make sure you practice drawing diffraction diagrams!

Answer 6

..

Question 7

What is refraction?

Answer 7

When a wave crosses a boundary between 2 substances (media) it changes direction and speed

Question 8

Refraction: If the light wave hits the boundary ‘face on’ it carries on in the [ ]

Answer 8

same direction.

Less dense -> Dense (more compact rays = slower)

Question 9

Refraction: If the light wave hits a different [ ] at an angle the wave [ ] = refraction

Answer 9

medium

changes direction