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Danyal Education
Light: Reflection and Refraction Assignment 1 (Pure)
Unit 14
Reflection and Refraction
beam
of light from a torch is aimed at
an
3. A
ruy of light is incident on a piece of glass
block as shown in the figure below. Which of the
l E
du
ca
tio
n
1. A
arrangement of four flat mirrors. Which diagram
shows the path that the light beam follows?
AB
following expressions should be used to calculate
the index ofthe glass block?
at
glass
D
C
I
40"
I
)
2. A ray of red light falls on a glass prism as shown
in the diagram below (The refractive index ofthe
Da
n
ya
glass is 1.5.)
Which of the following
shows the path of the
4.
A
sin 40"
C
....-srn 5U
sln JU
sin 30"
B
sin 50"
D
sin 30'
ri" 36t
rirZo"
()
Light can travel from one end ofan optical fibre
to the other, even if the fibre shows a curved path.
This is due to
A
B
C
D
5. A
dispersion of light
refraction oflight
the use of plane mirror
total internal reflection
ray of light strikes a plane mirror
()
M, at a
glancing angle of 40o. The mirror is now rotated
anti-clockwise through an angle of 10" to a new
position M, without changing the direction of
the incident light ray.
light through and out of the prism?
B
A
C
Because of a change in the position of the plane
mirror, the reflected light ray would turn through
D
an angle of
10" clockwise
20" clockwise
()
A
B
C
D
10" anticlockwise
20"
anticlockwise
-.
(
)
6.
The diagram below shows a ray of light
across a water-air boundary.
travelling
The diagram shows the image of the face of
clock seen in a plane mirror.
10
a
I
I
X
I
I
I
ar
Z
on
water
I
I
I
What is the correct time?
X
are the correct names of rays
and
A 3.35
c 7.20
Y and
angle Z?
Y
Refracted
Incident
Incident
Refracted
AngleZ
Incidence
Incidence
Critical
A I only
C II and III only
I
I
I
diamond
ai
69'
in front of
I
Determine the critical angle of diamond
27"
a plane mirror
ny
al
8. An object O is placed
I
I
B III only
D I, II and III only
(
MN
I
Ed
above is true?
(
The diagram shows a ray of light moving from
diamond to air.
()
7. the image formed by a plane mirror is always
I upright.
II virtual.
III as big as the object.
Which of the
11.
Critical
uc
A
B
C
D
X
Incident
Emergent
Refracted
Incident
B 5.40
D 8.25
ati
What
as shown in the diagram below. A student
moves her eye along the line XY to observe the
image of O.Identify the point (s) on the line XY
where the image of O cannot be seen.
A 27"
c 63"
B
D
12. the diagram below
from air into
ofthe glass?
glass.
650
()
shows a ray of light passing
What is the refractive index
MXN
Da
.o
A
C
1.,2and4only
3and4only
glass
B 1,3 and 4 only
(
D 4only
)
9. A man of height 1.8 m stands 0.5 m in front of
a vertical plane mirror. What is the minimum
length of mirror which will permit the man to see
his whole body?
A 0.5m
C 1.5m
air
40'
B 0.9m
D 1.8m
(
)
A
c
1.2
0.75
B
D
1.8
1.5
()
13.
The diagram below shows a plane mirror placed
at a distance of 400 cm in front of a man. If the
doctor's test card is fixed at 70 cm behind the
eyes of the man, what is the distance of the image
from the man?
15. A clear erect image can be obtained from a
prism periscope only if the prisms are correctly
positioned. The figure below shows four possible
arrangements of two prisms, with rays of light
drawn. Which is the correct arrangement?
A
D
B
70 cm
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tio
n
400 cm
(
I
A
C
B
D
470cm
870 cm
14.
76. A person stands at point X as shown in the
diagram below. Which of the pins (1, 2,3, 4,5)
800 cm
940cm
(
will the person be able to
see
in the mirror?
J
P,,
a
,I
glass
o
A
air
ya
ray of light in air is incident on a semicircular
block of glass at point P, as shown in the diagram
above. OP is a radius of the semicircle. Which of
the following ray diagrams shows how the ray will
pass through the block and into the air again?
,,B
Da
n
A
I
C
D
X
A
C
'1
Pins 1 and 3
Pins 2,3 and 5
B
D
2
Pins 2 and 4
Pins 2,4,and5
5
()
17. Which
one of the following is NOT a property of
the image of an object placed 72 cm in front of a
plane mirror?
A It is behind the mirror and laterally inverted.
B It is 12 cm from the mirror.
C A linejoining the top ofthe object to the
top of the image is perpendicular to the
plane of the mirror.
D It is real.
()
4
(
)
18. A
man whose eyes are 1.50 m from the ground
looks at his reflection in a vertical mirror 2.00 m
away.
The top and bottom of the mirror are 2.00 m
and 1.00 m from the ground respectively. What
distance, in metres, below his eyes can the man
see of himsel0
B
c 1.00
0.50
(
D 1.s0
optician's test card is 6xed 60 cm behind the
of a patient. A plane mirror is placed 250 cm
in front of the patient.What is the distance of the
image of the card from the patient's eyes?
A 250 cm
B 310 cm
eyes
C 500cm
figtre below shows a ray ofwhite light striking
a prism. Which of the following statements is
incidence?
20. A
source of
light
(
)
S is located 6 cm above a plane
S
o
Ed
uc
mirror and the reflected ray is detected 4 cm above
the mirror at a horizontal displacement of 12 cm.
The point ofreflection from A is
ati
o
true?
a light ray does not undergo bending at the
boundary between two media, what is its angle of
D90"
P
The light does not change direction at the
B
The light does not change direction at the
C
The light is split into colours only after
4cm
ITETTTETTfiTTT.ITIUTTI'IUU/
12 cm
6 cm
C
8 .5
21. the
cm
B
D
D
PQ
face QR.
reaches QR.
The light is split into colours at the face
B
7.2 cm
9.7 cm
al
A
()
PQ
()
the glass?
ny
Da
C
it
24. the diagram shows a light ray travelling from
glass to air. Which ratio is the refractive index of
diagrams below show the passage of light
through glass blocks. Which diagram is correct?
A
R
A
face
6cm
B
60"
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
D
45'
I
()
)
23. the
)
19. If
A0"845"
c60"
(
D 560cm
n
A 0.25
22. At
A
sin 40"
C
sin 30"
sfi20"
sin75"
B
sin 60"
p
sin 45'
sin 30"
.i"ZY
()
25. A
rectangular glass block when viewed normally
appears to be 5.0 cm thick. What is the actual
thickness of the block
the glass is 1.5?
if
A 0.3 cm
C 3.5cm
B 3.3 cm
D 7.5cm
28. A
ray of light is incident from below the surface
ofwater as shown in the diagram below. Using the
the refractive index of
(
values indicated, calculate the angle ofrefraction
(correct to 2 significant figures). The refractive
index of water is 1..3.
)
I
I
26- A ray of light passing from liquid X into air
I
n
I
makes an angle of incidence of 48" as shown in
the following diagram.
I
uc
ati
o
54'
I
:,::l'
:
',
A
:,:,
Liquid X
48'
l,:::
I
29.
the refractive index of the liquid is L.40,which
is the most probable emergent ray of light?
crrr
BII
Drv
27. At which point A, B, C or D, will
an observer at
the image of the object?
OB
plane mirror
('.
DC
OA
Da
ax
)
al
see
(
ny
X
39"
72"
(
A
B
C
D
with
from
an angle of incidence
air to glass, less than critical angle
air to glass, greater than critical angle
glass to air, less than critical angle
glass to air, greater than critical angle
Ed
If
water
Total. internal reflection takes place when light
passes
IV
I'
AI
B
D
27"
C 50"
r,::"
air
O object
()
30. A
photographer wishes to take pictures without
being noticed. He sets up two plane mirrors
together with his camera. Which arrangement
of mirrors will allow the photographer to take
pictures of someone behind the camera?
A
B
/
T
l.
\
/\
/\
C
D
T
\
A
/
T
/\
/
/
/
()
31.
The bottom surface ofa glass block is silvered to
act as a mirror. Which of the following diagrams
could represent the path of a light ray which
enters this block through the top surface?
A
B
Ifan observer peeps through the hole at the
mirror, the extent to which he can see the metre
rule is between the
A 0 cm and 90 cm mark
B 10 cm and 70 cm mark
C 20 cm and 50 cm mark
D 20 cm and 60 cm mark
34. The diagram
n
()
tio
shows a light ray passing through
a glass block. The phenomena at X is due to
D
C
)
32. An
object viewed in white light appears to be blue
I
II
white light contains various colours.
any colours striking it are converted into blue
light.
III only blue light is reflected.
B I only
A I, II and III
C I and III only D III only
0
(
X
10
Rule
(reading in cm)
20
hole
refraction oflight
total internal reflection oflight
bending of light
30
35. A ray of light
travels
)
with
passes
()
speed
z, through
into another medium
2, where it travels at speed zr.
The refractive index for medium 1 and medium 2
are n, and n, respectively. Which option correctly
compares the speeds and refractive indices for
each medium?
Refractive index
Speed oflight
z, is less thar, n,
A o, is less than z,
nris grezter than n,
B z, is less than o,
z, is less than n,
C tl2 is greater than z,
D z, is greater than o, nris greater rnr? r,
,
36. A ray of red light travels
M
40
dispersion of light
medium 1 and then
The diagram shows the cross section of a metre
rule XY with a small hole drilled at the 30 cm
mark. A plane mirror MN is placed in front of
the ruler and is parallel to it.
Da
ny
a
33.
A
B
C
D
l E
du
because
ca
X
lcln-
from air to glass
as
shown.
The critical angle for the glass is
10 cm
N
arr
glass
25"
50
----
normal
50'
60
70
80
90
100
A
c
33.5"
45.0"
B 4t.7"
D 45.2"
()
37. White light incident at an angle of 50" on the
A
B
C
D
will
passes from water into air, it is
refracted. What are the changes taking place?
A Its wavelength increases and its frequency
40. When light
be
deviated only
dispersed only
deviated and dispersed
totally internally reflected
decreases.
B
C
38. A pupil set up the apparatus shown below
D
to
increases.
Its speed increases and its wavelength
increases.
Its speed decreases and its wavelength
decreases.
al
Ed
uc
ati
o
investigate the relationship between the angle of
incidence (i ) and the angle ofrefraction (r) for a
ray oflight passing from air into glass.
Its wavelength decreases and its frequency
n
face of an equilateral prism made of glass
41.
Three objects, P,
Qand R,
(
)
are viewed through
a plane mirror as shown. When an obstacle is
moved towards the mirror, which one disappears
first and which one disappears last?
glass block
obstacle
light from a ray box
R
o
Which of the following
sin i against sin r?
is the correct graph
A
B
sin
of
\
OO
PQ
sin
ru
mrrror
sin
C
r
sin r
D
sin
Disappears first
Disappears last
AP
BP
CR
sin
a_
R
P
Da_
r
()
A.
A person standing at X in front of a plane mirror
would
see
an image of
The diagram shows a ray of light striking a plane
mlrror.
Y at position
C
B
Da
39.
sin
ny
sin r
()
R
X
mtrror
mrrror
()
is the angle ofincidence ifthe angle between
the incident and the reflected ray is 70"?
40"
What
A 35"
c7o"
B
D8oo
(
)
43. An object O is placed between
as shown.
image
At which position A,
D
C
two plane mirrors
B, C, or D will an
NOT be seen?
water
air
a
o
mirror
a
a
C
D
mirror
n
o
B
uc
ati
o
a
A
air
()
44.
46.
(
John is standing still in front of a mirror. In the
mirror, he sees Jane running towards him from
his back at a speed of 2 m s-1.What isJane's actual
speed?
A 1ms-1
C 4ms-1
perspex
arr
B 2ms1
D 8ms1
47. the diagram below
(
shows how the path
monochromatic ray of light differs when
of
it
passed through two prisms.
glass
Ed
air
agar
arr
glass
The given ray diagrams show what happens when
al
a narrow beam of light strikes the medium-air
interface of perspex, glass, and agar. Arrange the
three media in ascending order of their refractive
indices.
Da
ny
A
B
C
D
45.
Perspex, glass, agar
,, Plastic
Agar, perspex, glass
Glass, perspex, agar
Agar, glass,
(
perspex
)
The refractive index for water is 1.33. Which of
the following diagrams does NOT represent the
behaviour of light as it travels from water into
air?
A
B
I
I
I
I
I
0"
50"
water
water
air
arr
97
Why do the paths differ?
A
B
C
D
Glass is more transparent than plastic.
Plastic cannot totally refect light.
The plastic surface disperses the light.
The critical angle for plastic is greater than
(
that for glass.
)
a
is
passes through a semi-circular glass 51
block. In which of the following diagrams is the
critical angle marked correctly?
A
B
48. A ray of light
The diagram shows four lamps in front of and
behind an opaque plane mirror.The card prevents
the observer at X from seeing the lamps directly,
although the image of one lamp can be seen in
the mirror.
Which lamp's image can be seen in the mirror?
@
n
-@
A
C
()
Abeam oflight travels obliquelyfrom one medium
into another medium of higher refractive index.
All of the following are true statements about the
beam
A
B
C
D
50. A
oflight
except that
its speed increases
its wavelength decreases
its frequency remains the same
it bends towards the normal
I
card
X
Ed
uc
49.
ati
o
D
C
B
52.
(
)
()
@"
observer
The figure below shows a ray of light crossing the
boundary from medium 1 to medium 2.
ray of light travels from medium 1 to medium
and is totally internally refected as shown in
2
the diagram below. Which of the following
statements is correct?
B
medium
I
I
1
Medium Medium
Medium 2 has the highest optical density.
The ray will be refracted towards the normal
when it emerges from medium 2 to medium
Da
D
are plastic and air, which of the
following is correct?
7.
C
d.
If the two media
medium 3
A
B
medium 2
medium 2
ny
parallel
boundaries
medium
al
I
1
The ray will again undergo total internal
reflection at the boundary between medium 2
and medium 1.
If the angle of incidence at medium 2islarger,
the ray will be able to pass into medium 3.
()
A
B
C
D
1
2
Air
Plastic
Plastic
Air
Air
Plastic
Plastic
Air
Refractiveindex
ofplastic
sin F
sin a
sin F
sin a
sin a
tt"Fsin a
S"' B
)
53. A mirror
is tilted at an angle of 30" to the
bench.
A ray of light is directed so that it hits the mirror
at an angle of 20" to the surface of the mirror.
56.
The diagram shows a side view of a water-filled
aquarium PqRS.An electric lamp, surrounded
by a shield with a narrow slit, is immersed in one
corner of the aquarium at S. The light ray from
the slit shines on the water surface PQat an angle
of40"
70"
as shown.
mrrror
o
ati
on
P
40"
water
30'
R
If the refractive index is 1.33, which of the
What is the angle of refection?
A 20"
c 50"
B 30"
D 70"
diagrams below shows the correct path of this
light
(
54. Which
A
uc
one of the following is a property of the
image of an object placed 20 cm in front of a
plane mirror?
A It is on the mirror and laterally inverted.
B It is 10 cm from the mirror.
C A linejoining the top ofthe object to the
top of the image is perpendicular to the pane
of the mirror.
P
Ed
(
D It is real.
55. A
V
Da
R
B
P
B
C
P
al
ny
this?
o
)
coin is placed at the bottom ofa tall container
in the diagram. A person looks into the
container so that his line of sight includes point
P above the coin, and he cannot see the coin.
When water is slowly poured into the container,
the person suddenly sees the coin when the water
reaches a certain level. What is the reason for
as shown
o
S
D
o
P
()
n
A
B
Light is reflected from the surface of the water.
Light from the coin is refracted when it passes
from water into air.
C
The water provides a buoyant force to lift up
the coin.
Light from the eye is refracted when it passes
( )
from air to water.
D
ray?
57. Which of the following
light
passes
in the
light
glass
does
NOT
change
60. The diagram below shows an observer at O
as
looking straight through
window panel?
:x
AI
eye
fT
7n
XI
n
in its true position
61. A light pipe
Wavelengh
Direction
58. A girl of height
nearer
moved to the right
(
A
B
C
consists
)
D
1.6 m stands 0.5 m in front of
a vertical plane mirror. The bottom edge of the
high refractive index
low refractive index
high refractive index coated with layer of
glass of lower refractive index
low refractive index coated with layer ofglass
of higher refractive index
()
mirror is 0.8 m from the ground. What is the
minimum length of the mirror which will allow
the girl to see the whole of herselQ
B 0.8m
D 1.6m
A 0.5m
C 1.3m
59. A ray of light travels from air into
62. When light is refracted in passing from air
(
A
B
C
D
)
glass. The
ny
al
53.3"
(
its speed and frequency decrease
its speed and wavelength decrease
its speed and wavelength increase
its wavelength and frequency increase
()
63. An object is placed in front of a plane mirror
as
shown. Which point represents the position of
the image?
.A
)
Da
D 80.0"
Angle of
refraction
20.0"
60.0"
35.3"
to
glass
refractive index of the glass is 1.5. Which of the
following pairs could be values of the angle of
incidence and the angle ofrefraction?
Angle of
incidence
A 21.5"
B 40.0"
c 60.0"
(
of a central glass core of
Ed
u
Frequency
B
D
diminished
ca
:n
fI
tio
A
B
C
D
T-
Velocity
rectangular glass
90"
4
o
glass
A
C
a
block at an object P.To the observer, the object P
appears to be
.B
C
.D
100
'object
)
64. The diagram shows four
objects in front of a
mirror. The card prevents the observer's eye from
seeing the objects directly. Which object's image
can be seen in the mirror?
Which of the following statements is NOT true?
A No light is lost through the optical fibre.
B The light in the optical fibre obeys the laws
ofreflection.
C
A
B
D
66.
D
eye
The diagram below shows the view from the top
of a room PqRS which measures 15 m by 1,2 m.
An observer O stands at the center of the room
with his back to the wall RS.
Ed
uc
ati
mirror
card
on
CA
The refractive index ofX is greater than the
refractive index of Y.
The refractive index ofY is greater than the
( )
refractive index ofX.
o
15m
R
0
\
2m
o
)
65.
The diagram shows how light travels through the
optical fibre of an endoscope used to look into
stomach of ulcer patients. X represents the inner
material of the optic fibre while Y represents the
outer material.
P
The minimum width of
ny
al
Da
plane mirror,which must
be placed at eye level on the opposite wall, PQ
for the observer to be able to see the whole of the
image of the wall RS is
A 2m
C6m
X
a
S
B
4m
D
1.
2m
()