Laws of reflection and refraction

Question 1

Define and give example. Absorption.

Answer 1

In terms of light and lenses- when a ray of light enters a lens some of the light will not completely travel through the lenses.

Question 2

Define and give example. Deviation(angle of)

Answer 2

The angle a ray of light is changed from its original path

Question 3

Define and give example. Diffuse reflection.

Answer 3

A reflection from a rough surface- the reflection does not produce a clear image

Question 4

Define and give example. Incidence(angle of)

Answer 4

The angle which a ray of light makes with the surface of a refracting medium

Question 5

Define and give example. Reflection.

Answer 5

The return of light waves from a surface. The production of an image.

Question 6

Define and give example. Refraction.

Answer 6

The bending of light when going from one medium into another.

Question 7

Define and give example. Refraction(angle of).

Answer 7

The angle created when a ray of light passes from one medium into another.

Question 8

Define and give example. Specular reflection.

Answer 8

The forming of a clear image when light strikes a surface.

Question 9

Label diagram

Answer 9

A. Incident ray
B. Normal to the surface (for the first refraction)
C. Angle of incidence (for the first refraction)
D. Angle of deviation (for the first refraction)
E. Angle of refraction (for the first refraction)
F. Angle of incidence (for the second refraction)
G. Normal to the surface (for the second refraction)
H. Angle of refraction (for the second refraction)
I. Emergent ray
J. Where the ray would have been if the sheet of glass were not there
K. Displacement of the ray from the original path

Question 10

Why is the red pencil red?

Answer 10

It reflects red rays back toward the eye and absorbs all other rays of visible light

Question 11

Why is the blacktop black?

Answer 11

It does not reflect any rays back toward your eye; rather, it absorbs them all

Question 12

If a light beam passes through a green sunglasses lens, why will the exiting light be green?

Answer 12

The green rays are refracted through the lens and all other color rays are absorbed by the pigments in the lens material

Question 13

When a ray of light travel from air into water(which is denser than air) what happens to the ray of light if the ray is perpendicular to the surface?

Answer 13

It slows down but does not change direction. It is not deviated or displaced.

Question 14

When a ray of light travel from air into water(which is denser than air) what happens to the ray of light if the ray is not perpendicular to the surface?

Answer 14

It slows down and changed direction toward the normal. It deviates from its original path.

Question 15

When a ray of light travels from water into air (which is rarer than water) what happens to the ray of light if the ray is perpendicular to the surface?

Answer 15

It speeds up but does not change direction. It is not deviated or displaced.

Question 16

When a ray of light travels from water into air (which is rarer than water) what happens to the ray of light if the ray is not perpendicular to the surface?

Answer 16

It speeds up and changes direction away from the normal. It deviates from its original path.

Question 17

What does critical angle mean?

Answer 17

A light ray leaving a denser material for a rarer material that is at an angle to the normal that results in it traveling parallel to the surface of the material. If the angle of incidence is greater than the critical angle the ray will reflect inside the material and will not exit into the rarer material.

Question 18

If a light ray travels from air to water with an angle of incidence of 15 degrees and an angle of refraction of 11 degrees, how much did it deviate?

Answer 18

i=15
r=11
d=?

i=r+d
15=11+d
d=15-11
d=4

Question 19

If the light ray leaves the water traveling into air with an angle of incidence of 20 degrees and it is deviated by -7 degrees, what was the angle of refraction?

Answer 19

i=20
r=?
d=-7

i=r+d
20=r+(-7)
r-7=20
r=20+7
r=27

Question 20

The bending or redirection of a light wave when it passes a barrier without changing the medium in which it is traveling is called:

Answer 20

Diffraction

Question 21

When a light ray travel from one transparent medium to another, it changes direction. This bending of light, which results from the differences in density of different transparent materials, is called:

Answer 21

Refraction

Question 22

When a ray of light travels from one material to another, if its direction of travel is perpendicular or normal to the interface or junction between the materials, it will—

Answer 22

Change speed but not direction

Question 23

When a ray of light travels from a less dense (faster) material to a denser ( slower) material at an angle to the normal, it will—

Answer 23

bend toward the normal

Question 24

When a ray of light travels from a denser (slower) material to a less dense (faster) material at an angle to the normal, it will—

Answer 24

bend away from the normal

Question 25

When a ray of light leaves the crown glass, its angle with the normal to the surface is only 8 degrees. If it has an angle of refraction of 12 degrees, what is the angle of deviation when it leaves the glass?

Answer 25

-4 degrees

Question 26

If a ray of light is incident on a material at an angle of 18 degrees, and it is deviated by 7 degrees, what is its angle of refraction?

Answer 26

11 degrees

Question 27

When a ray of light travels from a denser medium to a less dense medium, r is greater than i and d is negative.

Answer 27

False

Question 28

When a ray of light travels from a less dense medium to a denser medium, r is less than i and d is positive.

Answer 28

True

Question 29

A ray of light travels from one material to another. The angle of incidence is 45 degrees and the angle of refractions 65 degrees. what is the angle of deviation?

Answer 29

-20 degrees

Question 30

A ray of light is deviated by -10 degrees from its path when it passes from one material into another material. If it was originally traveling at an angle of 29 degrees to the normal, it is—

Answer 30

exiting the denser material

Question 31

A ray of light traveling from air into crown glass (1.523) strikes the surface at an angle of 30 degrees. What will the angle of refraction be?

Answer 31

19 degrees

Question 32

If light travels through a liquid at 140,000 miles per second, what is the index of the liquid?

Answer 32

1.32

Question 33

If light traveling through air encounters a second medium which slows the light to 100,000 miles per second, what is the index of the second medium?

Answer 33

1.86

Question 34

What is the index of refraction of a refractive medium if the angle of incidence in air is 30 degrees and the angle of refraction is 15 degrees?

Answer 34

2.00

Question 35

What is the angle of refraction in water if the angle of incidence in air is 40 degrees?

Answer 35

29 degrees

Question 36

What is the index of refraction of a liquid if the angle of incidence in air is 35 degrees and the angle of refraction is 14 degrees?

Answer 36

2.37

Question 37

A ray of light exits from a material with an index of 1.80, traveling into air. If the angle of refraction is 20 degrees, what was the original angle of incidence?

Answer 37

11 degrees

Question 38

A ray of light exits from a material with an index of 1.00, traveling into water (1.33). If the angle of refraction is 20 degrees, what was the original angle of incidence?

Answer 38

27 degrees

Question 39

Which formula is used for calculating the angle of deviation?

Answer 39

i=r+d

Question 40

Which formula is used for calculating the index of refraction?

Answer 40

Speed of light in air/speed of light in medium

Question 41

Which formula is use for calculating the angle of refraction?

Answer 41

N1 sin i = N2 sin r