Unit 4.3

Question 1

Angle of reflection

Answer 1

The angle a reflected ray makes with the normal

Question 2

Angle of refraction

Answer 2

The angle a refracted ray makes with the normal

Question 3

Critical angle

Answer 3

The angle of the incidence of light that produces an angle of refraction of 90°

Question 4

Diffuse reflection

Answer 4

Reflection of light in many directions from an uneven surface, such as a book or a backpack

Question 5

Incident ray

Answer 5

Incoming ray

Question 6

Lateral inversion

Answer 6

The sideways or left-to-right rehearsal of an image in a plane mirror

Question 7

Law of reflection

Answer 7

The law stating that light is reflected at the same angle that it is incident, or i = r

Question 8

Normal

Answer 8

An imaginary line that is drawn at right angles to a surface that light is incident upon

Question 9

Plane mirror

Answer 9

A flat mirror

Question 10

Refraction

Answer 10

The bending of light as it enters of leaves different substances

Question 11

Refractive index

Answer 11

A measure of how easily light travels through a substance

Question 12

Regular reflection

Answer 12

Reflection of light from a very smooth surface, such as still water or a mirror; it produces a clear image

Question 13

Total internal reflection

Answer 13

When light is completely reflected from the boundary of two substances; it occurs when the angle of incidence is greater than the critical angle

Question 14

Virtual image

Answer 14

A type of image formed in which the rays of light do not actually meet, but only appear to meet at a point inside the mirror

Question 15

Angle of incidence

Answer 15

The angle an incoming ray makes with the normal