Download 554534 - Physics

Physics 534 – Refraction
Name:
Refraction – Assignment #1
1
Total:
An under-water diver directs a beam of light as shown in the diagram below.
r = 35 
air
sea
diver
i = 25 
What is the refractive index of the sea water, to two decimal places?
2
A transparent block having parallel faces is placed in a water fountain. A light ray originating
from the bottom of the fountain follows the path shown in the diagram.
35 º
n=?
transparent
block
eau
42 º
n = 1.33
fontain
side view
light
source
Calculate the index of refraction of the transparent block.
3
What should be the smallest angle of incidence with which a light beam is sent in an optical
fibre cable whose index of refraction is 1.6 for total internal reflection to occur?
/32
4
In the diagram below, an unidentified transparent material lies on top of a bed of fused
quartz. The absolute index of refraction of fused quartz is 1.46. When a light ray, in the
unidentified material, strikes the fused quartz, it undergoes total internal reflection.
Unidentified
Substance
Fused quartz
(n = 1.46)
Patricia came up with four hypotheses about the nature of the unidentified substance, using
the table below.
Absolute index of
refraction
Milieu
ice at –8°C
water
glass (crown)
zircon
Which of the following is the most likely hypothesis?
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1.31
1.33
1.52
1.90
A)
This material could also be fused quartz.
B)
This material could be zircon.
C)
This material could be ice at –8°C.
D)
This material could be any one of the four materials listed in the table.
The graphs below illustrate light rays that are passing from air into a transparent medium.
Which graph shows a light ray entering the medium with the highest refractive index?
A)
Air
C)
Transparent medium
Transparent medium
B)
Air
Transparent medium
Air
D)
Air
Transparent medium
6
A transparent block that is made from three parallel solid substances glued together (A, B
and C) is immersed in a liquid. The indices of refraction are different for each substance. A
light ray is directed toward the block, as shown in the diagram.
Which of the following statements is correct?
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A)
n1  n2  n3
B)
n1  n2  n3
C)
n1  n2  n3
D)
n1  n2  n3
The index of refraction for a certain kind of glass is 1.67 for blue light and 1.61 for red light.
A beam containing these two colours hits the glass with an angle of incidence of 45°.
45°
air n = 1.00
glass
Red
Blue
Calculate the angle between the two refracted rays.
8
Light passes from air into an unknown medium and is reflected from a plane mirror.
air
n1 = 1.00
40°
n2 = ?
70°
Plane mirror
What is the index of refraction (n2) for the unknown medium?
9
A fish located 15 m from shore can just see the top of a sign 1.5 m high located 5.0 m from
the edge of the water. The index of refraction of water is 1.33.
At what depth below the surface of the water is the fish
10
In the laboratory, a light ray passes
through two liquids, one floating on top of
the other, in a beaker. The angle of
refraction in the water is 25°.
Air : n = 1.0
Mineral oil : n = 1.46
Water : n = 1.33
25°
What is the value of the angle of incidence A?
11
Which medium would have the smallest critical angle, θc, in the situation shown below?
Normal
nair = 1.00
Air
Medium X
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A)
Diamond
(n = 2.42)
B)
Glycerin
(n = 1.47)
C)
Lucite
(n = 1.51)
D)
Water
(n = 1.33)
The drawing on the right represents a
water droplet.
Light, inside the water droplet, hits the
surface between water and air.
c
Water Droplet
n = 1.33
Air
n = 1.00
θ
At what angle () must light hit the surface in order to totally reflect?
13
A)
At 48.8°
B)
At an angle greater than 48.8°
C)
At an angle less than 48.8°
D)
At any angle between 0° and 90°
Ally and Conor perform an experiment in the lab. They place a light source at the bottom of a
container filled with an unknown liquid. The light source in the unknown liquid gives off a ray
that passes into air (as shown) and the results are recorded in the table below.
65.0°
Air ( n= 1.00)
40.0°
Unknown liquid
Light Source
Based on the data collected, Ally and Conor calculated the critical angle of a ray in this set
up. What is the critical angle of a ray travelling from the unknown liquid into air?
14
Standing beside the Trevi Fountain in Rome, you see a coin at the bottom of the water. A ray
of light from the coin hits at your eye, forming an angle of 42 with the surface of the water.
Observer
Normal
n air = 1.00
42°
n water= 1.33
Object
What is the angle of incidence of the light ray?
15
A diamond is placed in a container of water as shown in the diagram below.
A light ray, from air, hits the water with an angle of incidence of 60° before reaching the
water-diamond surface.
Incident ray
60°
Air
Water
nair = 1.00
nwater = 1.33
Diamond
R
ndiamond= 2.42
What is the angle of refraction, R, once the light ray enters the diamond?
16
Grant decided to build a decorative lamp. He placed a sealed light at the bottom of a glass
container filled with a transparent oil (n= 1.56). The bottom of the container is flat &
horizontal. Two mirrors are attached to the bottom and to one side of the container, as
illustrated.
Grant plans to have the beam of light reflect, in turn, from the surface, from mirror 1, from
mirror 2, and then from the surface again. He wants all of the light to remain in the lamp as it
reflects from the surface at point P.
What is the minimum angle of incidence of the initial light beam that will make the light reflect
the surface from point P?