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Free download in PDF Lenses & Mirrors General Knowledge Multiple Choice Questions(MCQs) & Answers for competitive exams. These short objective type questions with answers are very important for Board exams as well as competitive exams. These short solved questions or quizzes are provided by Gkseries.
(1)
An object is placed at the focus of a concave mirror. The image will be
[A]
real, inverted, same size at the focus
[B]
real, upright, same size at the focus
[C]
virtual, inverted, highly enlarged at infinity
[D]
real, inverted, highly enlarged at infinity
Answer: real, inverted, highly enlarged at infinity
(2)
The human eye is like a camera and hence it contains a system of lens. The eye lens forms
[A]
a straight or upright, real image of the object on the retina
[B]
an inverted, virtual image of the object on the retina
[C]
an inverted, real image of the object on the retina
[D]
a straight or upright, real image of the object on the iris
Answer: an inverted, real image of the object on the retina
(3)
The radius of curvature of a plane mirror
[A]
is zero
[B]
is infinity
[C]
can be anywhere between zero and infinity
[D]
None of the above
(4)
The ratio of the focal length of the objective to the focal length of the eyepiece is greater than one for
[A]
a microscope
[B]
a telescope
[C]
both microscope and telescope
[D]
neither microscope nor telescope
(5)
The mirror used for the head light of a car is
[A]
spherical concave
[B]
plane
[C]
cylindrical
[D]
parabolic concave
Answer: parabolic concave
(6)
The image formed by a convex mirror of a real object is larger than the object
[A]
when u < 2f
[B]
when u > 2f
[C]
for all values of u
[D]
for no value of u
Answer: for no value of u
(7)
What is the power of the lens, if the far point of a short-sighted eye is 200 cm?
[A]
-0.5 D
[B]
2 D
[C]
1 D
[D]
-1.5 D
(8)
Which one among the following is used to make periscope?
[A]
Concave lens
[B]
Concave mirror
[C]
Plane mirror
[D]
None of the above
(9)
A spherical air bubble is embedded in a piece of glass. For a ray of light passing through the bubble, it behaves like a :
[A]
converging lens
[B]
diverging lens
[C]
plano-diverging lens
[D]
plano-converging lens
(10)
Suppose you are standing 1 m in front of a plane mirror. What should be the minimum vertical size of the mirror so that you can see your full image in it?
[A]
4 m
[B]
0.30 m
[C]
twice your height
[D]
half of your height
Answer: half of your height
(11)
What would be the number of images formed of an object in two mirrors placed at right angles to each other?
[A]
two
[B]
three
[C]
four
[D]
six
(12)
A number of images of a candle flame can be seen in a thick mirror. The brightest image is -
[A]
second
[B]
third
[C]
last
[D]
fourth
(13)
What type of mirror is used in a view finding mirror of a vehicle?
[A]
Concave mirror
[B]
Convex mirror
[C]
Plane mirror
[D]
Paraboloidal mirror
(14)
The head mirror used by E.N.T doctors is -
[A]
Plane
[B]
Convex
[C]
Concave
[D]
Plano-convex
(15)
An object is kept 5 cm in front of a concave mirror of focal length of 15 cm. What will be the nature of the image?
[A]
virtual, not magnified
[B]
virtual, magnified
[C]
real, magnified
[D]
real not magnified
Answer: virtual, magnified
(16)
What kind of lens is used by short-sighted persons?
[A]
convex
[B]
concave
[C]
cylindrical
[D]
compound
(17)
How far must an object be from a concave mirror if the image formed is to be inverted?
[A]
less than its focal length
[B]
exactly at its focal length
[C]
more than its focal length
[D]
None of the above
Answer: more than its focal length
(18)
How far must a girl stand in front of a concave spherical mirror of radius 120 cm to see an erect image of her face four times its natural size?
[A]
40 cm from the mirror
[B]
45 cm from the mirror
[C]
50 cm from the mirror
[D]
55 cm from the mirror
Answer: 45 cm from the mirror
(19)
An optician prescribes a power = - 0.5 dioptre. The corresponding lens must be a
[A]
convex lens of focal length 2 m
[B]
convex lens of focal length 50 cm
[C]
concave lens of focal length 2 m
[D]
concave lens of focal length 50 cm
Answer: concave lens of focal length 2 m
(20)
What kind of image is created by a concave lens?
[A]
upright and smaller
[B]
inverted and smaller
[C]
inverted and larger
[D]
upright and smaller
Answer: upright and smaller
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