CBSE Class 10 Science The Human Eye and the Colourful World MCQs

Question : The defect of the eye in which the eyeball becomes too long is
(a) myopia
(b) hypermetropia
(c) presbyopia
(d) cataract
Answer : A

Question : The least distance of distinct vision for a young adult with normal vision is about
(a) 25 m.
(b) 2.5 cm.
(c) 25 cm.
(d) 2.5 m.
Answer : A

Question : The human eye can focus objects at different distances by adjusting the focal length of the eye lens. This is due to
(a) presbyopia
(b) accommodation
(c) near-sightedness
(d) far-sightedness
Answer : B

Question : The change in focal length of an eye lens is caused by the action of the
(a) pupil.
(b) retina.
(c) ciliary muscles.
(d) iris.
Answer : C

Question : The human eye forms the image of an object at its
(a) cornea.
(b) iris.
(c) pupil.
(d) retina.
Answer : D

Question : The amount of light entering the human eye is controlled by
(a) Ciliary muscles
(b) Pupil
(c) Cornea
(d) Iris
Answer : B

Question : Which of the following phenomenon contributes significantly to the reddish appearance of the sun at sunrise or sunset?
(a) Dispersion of light
(b) Scattering of light
(c) Total internal Reflection
(d) Reflection of light from the earth
Answer : B

Question : Assertion: The near-point of a hypermetropic eye is more than 25 cm away.
Reason: Hypermetropia is corrected using spectacles containing concave lenses.
(a) Both A and R are true and R is the correct explanation of (a)
(b) Both A and R are true but R is not the correct explanation of (a)
(c) A is true but R is false.
(d) A is false but R is true.
(e) Both A and R are false.
Answer : C

Question : The change in the focal length of human eye is caused due to
(a) Ciliary muscles
(b) Pupil
(c) Cornea
(d) Iris
Answer : A

Question : A person cannot see the distant objects clearly (though he can see the nearby objects clearly). He is suffering from the defect of vision called:
(a) Cataract
(b) Hypermetropia
(c) Myopia
(d) Presbyopia
Answer : C

Question : When white light enters a prism, it gets split into its constituent colours. This is due to
(a) different refractive index for different wavelength of each colour
(b) each colours has same velocity in the prism.
(c) prism material have high density.
(d) Scattering of light
Answer : A

Question : The image formed on the retina of the human eye is
(a) virtual and inverted
(b) real and inverted
(c) real and erect
(d) virtual and erect
Answer : B

Question : The defect of vision in which the person is able to see distant object distinctly but cannot see nearby objects clearly is called
(a) Long-sightedness
(b) Far-sightedness
(c) Hypermetropia
(d) All of the above
Answer : D

Question : At noon, the Sun appears white as
(a) blue colour is scattered the most
(b) red colour is scattered the most
(c) light is least scattered
(d) all the colours of the white light are scattered away
Answer : C

Question : The air layer of atmosphere whose temperature is less then the hot layer behave as optically
(a) denser medium
(b) rarer medium
(c) inactive medium
(d) either denser or rarer medium
Answer : A

Question : Bi-focal lens are required to correct
(a) astigmatism
(b) coma
(c) myopia
(d) presbyopia
Answer : D

Question : The image formed on the retina of the human eye is
(a) virtual and inverted
(b) real and inverted
(c) real and erect
(d) virtual and erect
Answer : B

Question : The image formed on the retina of human eye is
(a) virtual and erect
(b) real and inverted
(c) virtual an inverted
(d) real and erect
Answer : B

Question : The persistence of vision for normal eye is
(a) (1/10) th of a second
(b) (1/16) th of a second
(c) (1/6) th of a second
(d) (1/18) th of a second
Answer : B

Question : Which of the following colours is least scattered by fog, dust of smoke?
(a) Violet
(b) Blue
(c) Red
(d) Yellow
Answer : C

Question : Which part of the eye refracts light entering the eye from external objects?
(a) Lens
(b) Cornea
(c) Iris
(d) Pupil
Answer : B

Question : The change in the focal length of human eye is caused due to
(a) ciliary muscles
(b) pupil
(c) cornea
(d) iris
Answer : A

Question : The coloured light that refracts most while passing through a prism is
(a) Yellow
(b) Violet
(c) Blue
(d) Red
Answer : B

Question : Long-sightedness or hypermetropia can be corrected by
(a) Contact lens
(b) Concave lens
(c) Convex lens
(d) Bifocal lens
Answer : C

Question : The least distance of distinct vision for a young adult with normal vision is
(a) 25 m
(b) 20 m
(c) 25 cm
(d) 20 cm
Answer : C

Question : The amount of light entering the human eye is controlled by
(a) Ciliary muscles
(b) Pupil
(c) Cornea
(d) Iris
Answer : B

Question : The colour of sky is blue during day time, red during sunset and black at night. This is due to
(a) Scattering of light
(b) Small particles present in atmosphere
(c) Atmospheric refraction
(d) All of the above.
Answer : D

Question : The phenomenon of light responsible for the working of the human eye is
(a) reflection
(b) refraction
(c) power of accommodation
(d) persistence of vision.
Answer : B

Question : The focal length of human eye lens can be changed due to
(a) Iris
(b) Ciliary muscles
(c) Contact lens
(d) Spectacles
Answer : B

Question : The glass has greater refractive index for
(a) Violet light
(b) Green light
(c) Blue light
(d) Red light
Answer : A

Question : A student of class 10, is not able to see clearly the black board Question when seated at a distance of 5 m from the board, the defect he is suffering from is
(a) Myopia
(b) Hypermetropia
(c) Presbyopia
(d) Astigmatism
Answer : A

Question : The component of white light with greatest wavelength is
(a) Violet
(b) Red
(c) Green
(d) Blue
Answer : B

Question : The part of eye that determines the colour of the eye of a person is
(a) Pupil
(b) Cornea
(c) Retina
(d) Iris
Answer : D

Question : The light sensitive cell present on retina and is sensitive to the intensity of light is:
(a) cones
(b) rods
(c) both rods and cones
(d) none of these
Answer : B

Question : Colour blindness is caused due to
(a) lack of rod cells
(b) absence of optic nerve
(c) lack or cone cells
(d) none of these
Answer : C

Question : The clear sky appears blue because
(a) blue light gets absorbed in the atmosphere.
(b) ultraviolet radiations are absorbed in the atmosphere.
(c) violet and blue lights get scattered more than lights of all other colours by the atmosphere.
(d) light of all other colours is scattered more than the violet and blue colour lights by the atmosphere.
Answer : C

Question : A person cannot see distinctly objects kept beyond 2 m. This defect can be corrected by using a lens of power
(a) + 0.5 D
(b) – 0.5 D
(c) + 0.2 D
(d) – 0.2 D
Answer : D

Question : The eye defect represented by the figure is

(a) Myopia
(b) Hypermetropia
(c) Cataract
(d) Presbyopia
Answer : A

Question : The following illustration represents the

(a) Correction of eye defect
(b) working of a simple microscope
(c) both (a) and (b)
(d) none of the above
Answer : B

Question : At noon, the Sun appears white as
(a) blue colour is scattered the most
(b) red colour is scattered the most
(c) light is least scattered
(d) all the colours of the white light are scattered away
Answer : C

Question .When a person is myopic, he/ she can clearly see
(a) both nearby and far off objects
(b) Only nearby objects
(c) only far off objects
(d) Neither nearby nor far off objects
Answer : B

Question : Which of the following colors is least scattered by fog, dust of smoke?
(a) Violet
(b) Blue
(c) Red
(d) Yellow
Answer : C

Question : Blue colour of the sky is due to the phenomenon of:
(a) Reflection of light
(b) Refraction of light
(c) Dispersion of light
(d) Scattering of light
Answer : D

Question : The splitting of white light into different colours on passing through a prism is called
(a) reflection
(b) refraction
(c) dispersion
(d) deviation
Answer : C

Question : The least distance of distinct vision for an eye lens is caused by the action of the
(a) 25 m
(b) 2.5 cm
(c) 25 cm
(d) 2.5 m
Answer : C

Question . The black opening between the aqueous humour and the lens is called
(a) retina
(b) iris
(c) cornea
(d) pupil
Answer : D

Question : The least distance of distinct vision for a young adult with normal vision is :
(a) 25m
(b) 20m
(c) 25cm
(d) 20cm
Answer : C

Question : Which of the following colours is least scattered by fog, dust or smoke :
(a) Violet
(b) Blue
(c) Red
(d) Yellow
Answer : C

Question : The variation of focal length to form a sharp image on the retina is called ----.
(a) Accommodation
(b) Aperture
(c) Retina control
(d) Sutter
Answer : A

Question : The part of eye that is a messenger of electrochemical signals from eye to brain is called :
(a) Blood vessel
(b) Optic nerve
(c) Iris
(d) CorneaA
nswer :  B

Question : The human eye forms the image of an object at its
(a) Iris
(b) Pupil
(c) Cornea
(d) Retina
Answer : D

Question : The __ colour is at the top and ____ colour is at the bottom of spectrum.
(a) Red, Violet
(b) Red, Blue
(c) Violet, red
(d) None
Answer : C

Question : When white light enters a prism, it gets split into its constituent colours. This is due to
(a) different refractive index for different wavelength of each colour
(b) each colours has same velocity in the prism.
(c) prism material have high density.
(d) Scattering of light
Answer : A

Question : Cornea is a transparent spherical structure which ____
(a) Reflects light
(b) Refracts light
(c) Scatters light
(d) None
Answer : D

Question : Long sightedness is caused by eyeball being too short. It can be corrected by :
(a) Using convergent lens
(b) Plane mirror
(c) Divergent lens
(d) None
Answer : A

Question : When an object moves towards a convex lens the size of image _____.
(a) Decreases
(b) Increases
(c) First decreases then increases
(d) Remains the same
Answer : D

Question : At a particular minimum value of angle of deviation, the refracted ray becomes :
(a) Parallel to base of prism
(b) Perpendicular to base of prism
(c) Inclined at 45degrees w.r.t base of prism
(d) None
Answer : A

Question : The image formed by retina of human eye is :
(a) Permanent
(b) temporary
(c) Blurred
(d) None
Answer : B

Question : Refraction of light by the earth’s atmosphere due to variation in air density is called
(a) atmospheric reflection
(b) atmospheric dispersion
(c) atmospheric scattering
(d) atmospheric refraction
Answer : D

Question : Twinkling of stars is due to atmospheric
(a) dispersion of light by water droplets
(b) refraction of light by different layers of varying refractive indices
(c) scattering of light by dust particles
(d) internal reflection of light by clouds.
Answer : B

Question : The muscular diaphragm that controls the sides of pupil is :
(a) Cornea
(b) Ciliary muscles
(c) Iris
(d) Retina
Answer : C

Question : The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light
(a) is scattered the most by smoke or fog.
(b) is scattered the least by smoke or fog.
(c) is absorbed the most by smoke or fog.
(d) moves fastest in air.
Answer : B

Question : Image formed in normal eye of human is:
(a) on retina
(b) beyond retina
(c) behind retina
(d) at infinity
Answer : A

Question : One cannot see through the fog, because
(a) refractive index of the fog is very high
(b) light suffers total reflection at droplets
(c) fog absorbs light
(d) light is scattered by the droplets
Answer : D

Fill in the Blank

Question. The ability of the eye to focus both near and distant objects, by adjusting its focal length, is called the ..........
Answer : Accommodation of the eye.

Question. .......... is the inside surface of the rear part of the eyeball where the light entering the eye is focused.
Answer : Retina

Question. The splitting of white light into its component colours is called ...........
Answer : Dispersion

Question. The defect of the eye due to which a person is unable to distinguish between certain colours, known as ..........
Answer : Colour blindness

Question. The smallest distance, at which the eye can see objects clearly without strain, is called the .......... of the eye.
Answer : Near point

Question. The eye which cannot simultaneously see with the same distinctness all objects or lines making different inclinations is said to suffer from ..........
Answer : Astigmatism.

Question. ..............causes the blue colour of sky and the reddening of the Sun at sunrise and sunset.
Answer : Scattering of light

Question. The middle point of the iris has a hole, which is called ..........
Answer : Pupil

Question. The eye which suffers from myopia as well as from hypermetropia is said to suffer from ..........
Answer : Presbyopia

True or False

Question. Clouds look white because water droplets of clouds scatter all colours of light equally.
Answer : True

Question. The sun is visible two minutes before the actual sunrise due to atmospheric refraction.
Answer : True

Question. Danger signal lights are red in colour.
Answer : True

Question. The colour of the scattered light does not depend on the size of the scattering particles.
Answer : False

Question. Colour blindness is a genetic disorder which occurs by inheritance.
Answer : True

Question. Water droplets act as tiny prism in the formation of rainbow.
Answer : True

Question. The part of human eye that determines the colour of a person’s eye is known as cornea.
Answer : False

Question. The eye which cannot see distant objects clearly is said to suffer from myopia.
Answer : True

Question. The focal length of a given lens depends on the surrounding medium.
Answer : True

Question. Te transparent spherical membrane covering the front of the eye is known as cornea.
Answer : True

Question. To see an object comfortably and distinctly, you must hold it at about 25 cm from the eyes.
Answer : True

Question. The angle between incident ray and emergent ray is called angle of deviation.
Answer : True

Question : The ability of the eye to adjust its focal length according to the distance of the object and intensity of light falling on it is called