Topic 3 - Reflection and Refraction

Question 1

what is a diffuse reflection?

Answer 1

when light is reflected from an uneven surface so reflects at different angles

Question 2

what is a clear reflection?

Answer 2

light reflecting form an even surface so is reflected at the same angle

Question 3

what is the law of reflection?

Answer 3

angle of incidence = angle of reflection

Question 4

what is the point of incidence?

Answer 4

where the wave hits the boundry

Question 5

what is the normal?

Answer 5

an imaginary line perpendicular to the point of incidence

Question 6

what is the angle of incidence?

Answer 6

the angle between the incoming wave and the normal

Question 7

how are waves refracted?

Answer 7

they travel at different speeds through substances with different densities, so are refracted when a wave crosses a boundary between two substances.

Question 8

what is a ray diagram?

Answer 8

a ray diagram shows the path that a wave travels

Question 9

how would you draw a ray diagram for a reflected light ray?

Answer 9

1. draw the boundry between the two materials and the normal
2. draw the incident ray that meets the normal at the boundry
3. draw the reflected ray on the other side of the boundry. if the material is denser than the first, the refracted ray bends towards the normal

Question 10

how would you see refraction through a glass block?

Answer 10

1. shine a light ray at an angle into the block
2. trace the incidnet and emergent rays and remove the block. draw rhe refected ray by joining the two rays up
3. when entering the block the light bends towards the normal as it slows down

Question 11

what happens when you shine white light into a trianglar prism?

Answer 11

different wavelengths of light refract by different amounts, so different colours of light are emitted out of the prism