v ( lam b d a)

f = no. of oscillations per s [ f hertz (Hz)] = frequency of oscillation

Is the velocity of the wave shown above

2 2

12

(a) (b) 2

(c) (d)

(e)

v f v af

fv v

f

fv

For reflection of light, we have the situation shown in Figure 1. The two plane mirrors in Figure 2 are at 90o to each other, and the incident light beam is in the plane of the screen

30o

incidentbeam

By making a careful sketch of the reflection beam in Figure 2, decide which best describes its final outgoing path.

Figure 1 Figure 2

d) none of the above

a) b) c)

The index of refraction of glass decreases with increasing wavelength in the optical region

Red light has a longer wave length then violet light

Which of the following best represents the refraction of white light (contains all colors red to violet)

air

glass

white light

redviolet

air

glass

white light

redviolet

(b)(a)

medium 1

medium 2 refracted

1

2

n n2 1 2 2sin sin Snell’s law for refraction of light is

where:

a

b

c

d

)

)

)

)

N o ne o f the ab o ve

1 2

1 2

1 2

velocity in vacuum

velocity in medium

cn

v

If the velocity of light is greater in medium 2 than medium 1, is

n1

n2 Total internalreflection11

Total internal reflection occurs when

11 2 1 2 1

2

21

1

a) b) c) sin

d) sin e) b & c

nn n n n

n

n

n

air

water1

2

h

For the refraction of light from the fish on the right, which is correct?

2 1 2

2 1 2 1

(a) (b) 0

(c) (d)

Use a sketch of the path of 2 light rays from the same spot on the fish to decide if a person in the air sees the fish at depth d where

air

waterh

(a) d < h

(b) d = h

(c) d > h

(d) need more information

From a sketch roughly to scale, use principal rays to determine weather the position of the image is approximately at

F1 F2

A B C D

(a) A (b) B (c) C (d) D

1. Is the image (a) virtual (b) real

2. Is the image (a) upright (b) inverted

3. Is the magnification of the image

(a) >1 (b) 1 (c) <1

4. Is the image distance

(a) negative (b) positive

From a sketch roughly to scale, use principal rays to determine whether the position of the image is approximately at

(a) A (b) B (c) C (d) D (e) E

1. Is the image (a) virtual (b) real

2. Is the image (a) upright (b) inverted

3. Is the magnification of the image

(a) >1 (b) 1 (c) <1

4. Is the image distance

(a) negative (b) positive

F1 F2A B C D E

1. For the thin lenses above, roughly where is the final image from the two lenses?

(a) A (b) B (c) C (d) D (e) E

2. The image distance for lens #2 is

(a) positive (b) negative

O

A B C D E

# 1 # 2

F1

F1

F2 F2

F1 shows the focal points of lens #1, and F2 for lens #2.

Lensmaker’s equation

R is positive if C is in back of the surface.

1. What is the focal length of the lens above?

(a) 0.025 cm (b) 40 cm (c) -40 cm

(d) 0.075 cm (e) 13.3 cm

11

1 1

1 2fn

R R

( )

R = 10 cm R = 20 cm

n = 1.5air

Lensmaker’s equation

R is positive if C is in back of the surface.

1. What is the focal length of the lens above?

(a) 0.050 cm (b) 20 cm (c) -20 cm

(dc) -0.05 cm (e) not enough info to tell

11

1 1

1 2fn

R R

( )

R = 10 cm

n = 1.5

air

Lens 1 Lens 2

Is Lens 1 (a) Converging (b) Diverging

(c) Neither ?

Is Lens 2 (a) Converging (b) Diverging

(c) Neither ?

airair

11

1 1

1 2fn

R R

( )

air

Lens 1 Lens 2

Is Lens 1 (a) Converging (b) Diverging

(c) Neither ?

Is Lens 2 (a) Converging (b) Diverging

(c) Neither ?

air

11

1 1

1 2fn

R R

( )

10 cm

n =1.3 n =1.5

|R| = 5 cm

A

B

Where is the image?

(a) A (b) B

Water

Glass rod

15 cm

oil n =1.3glass n =1.5

|R| = 10 cm1 2 2 1

1

2

(1)

(2)

n n n n

s s Rn s

Mn s

1. Is R (a) positive (b) negative

4. With a careful drawing and Snell’s law can you tell whether the image is in front of or behind the surface, without using Equation 1? (Answer (a) for yes and (b) for no)

3. What is the magnification? (a) < 1 (b) >1

2. Where is the image formed from the glass surface

(a) to right of surface (b) to left of surface