Class-8 Light And Vision MCQs with Answers

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 MCQs With Answers

Question 1.

The impression or sensation remains on the retina for about how may seconds even after removal of the object ?

A.1 second

B.1/16th of a second

C.16 seconds

D.1 minute

ANSWER: B

Question 2.

The cells present in the retina of eye and responding to intensity of light are:

A.Rod-shaped cells

B.Both of these

C.Cones

D.None of these

ANSWER:  A

Question 3.

The cells present in the retina of eye and responding to colour are:

A.Rod-shaped cells

B.Both of these

C.Cones

D.None of these

ANSWER:  C

Question 4.

The disease of eye in which crystalline lens becomes hazy or even opaque due to development of membrane over it is :

A.Myopia

B.Cataract

C.Hypermetropia

D.Presbyopia

ANSWER: B

Question 5.

Angle of incidence is equal to the angle of reflection:

A.Always

B.Sometimes

C.Under special conditions

D.Never

ANSWER: A

Question 6.

Image formed by a plane mirror is:

A.Virtual, behind the mirror and enlarged

B.Virtual, behind the mirror and of the same size as the object

C.Real at the surface of the mirror and enlarged .

D.Real, behind the mirror and of the same size as the object

ANSWER: B

Question 7. Reflection is:

A.absorption of light rays by the surface of an object

B.passing of light rays through the surface of an object

C.bouncing back of light rays from the surface object

D.None of these

ANSWER: C

Question 8.

Splitting of light into its colours is known as:

A.spectrum

B.dispersion

C.rainbow

D.none of these

ANSWER: B

Question 9.

Which of the following is not a source of light:

A.Tubelight

B.The sun

C.The moon

D.Fire fly

ANSWER: C

Which type of mirror is used to obtain a virtual, laterally inverted image and equal in size of an object ?

A.plane mirror

B.concave mirror

C.convex mirror

D.all of these

ANSWER: B

Question 11.

The angle between incident ray and normal is called the angle of:

A.reflection

B.incidence

C.refraction

D.none of these

ANSWER: B

Question 12.

The lens present in eye is:

A.convex lens

B.concave lens

C.either convex or concave

D.none of these

ANSWER: A

Question 13.

Kaleidoscope is based on the pattern of:

A.reflection

B.multiple reflection

C.spectrum

D.diffused reflection

ANSWER: B

Question 14.

When two mirrors are placed parallel to each other, and a candle is placed in the centre of the mirrors no. of images will be formed.

A.infinite

B.three

C.six

D.no image will be formed

ANSWER: A

Question 15.

The difference in the colour of the eye is due to difference in:

A.retina

B.iris

C.sclera

D.pupil

ANSWER: B

Question 16.

Beam of light striking the reflecting surface is called:

A.Reflecting ray

B.Incident ray

C.Refracted ray

D.Normal

ANSWER: B

Question 17.

Beam of light, bounced back by the surface after falling on it is called

A.Reflecting ray

B.Incident ray

C.Refracted ray

D.normal

ANSWER: A

Question 18.

Band of seven colours is called:

A.  Dispersion

B.  Spectrum

C. VIBGYOR

D. Both B. and C.

ANSWER: B

Question 19.

Rainbow is formed after rain due to

A. Dispersion

C. Reflection

B. Multiple reflection

D. Refraction

ANSWER: A

Question 20.

Front bulged part of the eyeball is called:

A.Cornea

B.Choroid

C.Pupil

D.Retina

ANSWER: A

Question 21.

Visually impaired people can read and write using:

A.Degital pens

B.Electronic writer

C.Braille system

D.Hearing aids

ANSWER: C

Question 22.

The amount of light entering the eye is regulated by:

A.Iris

B.Ciliary muscles

C.Pupil

D.Lens

ANSWER: A

Question 23.

The focal length of the eye-lens is changed by:

A.Retina

B.Iris

C.Pupil

D.Ciliary muscles

ANSWER: D

Question 24.

The human eye forms the image of an object at its:

A.Iris

B.Cornea

C.Pupil

D.Retina

ANSWER: D

Question 25.

Far point of a normal human eye is situated at:

A.25 m

B.25 mm

C.25 cm

D.Infinity

ANSWER: D

Question 26.

The least distance of distinct vision for a young adult with normal vision is:

A.25 m

B.25 mm

C.25 cm

D.Infinity

ANSWER: C

Question 27.

The near point at the age of 60 years is:

A.25 cm

B.25 m

C.200 cm

D.Infinity

ANSWER: C

Question 28.

The massage of image formation is conveyed to the brain by:

A.Cornea

B.Ciliary muscles

C.Yellow spot

D.Optical nerve

ANSWER: D

Question 29.

A person who cannot see the distant objects is said to be suffering from:

A.Myopia

B.Presbyopia

C.Hypermetropia

D.Astigmatism

ANSWER: A

Question 30.

A person who cannot see the near by objects is said to be suffering from:

A.Myopia

B.Presbyopia

C.Hypermetropia

D.Astigmatism

ANSWER:  C


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