# MCQs For NCERT Class 10 Science Chapter 11 Human Eyes and Colourful World

Please refer to the MCQ Questions for Class 10 Science Chapter 11 Human Eyes and Colourful World with Answers. The following Human Eyes and Colourful World Class 10 Science MCQ Questions have been designed based on the current academic year syllabus and examination guidelines for Class 10. Our faculty has designed MCQ Questions for Class 10 Science with Answers for all chapters as per your NCERT Class 10 Science book.

## Human Eyes and Colourful World Class 10 MCQ Questions with Answers

Please see below Human Eyes and Colourful World Class 10 Science MCQ Questions, solve the questions and compare your answers with the solutions provided below.

Question: Study the following ray diagram :

In this diagram, the angle of incidence, the angle of emergence and the angle of deviation respectively have been represented by :
(a) y, p, z
(b) x, q, z
(c) p, y, z
(d) p, z, y

C

Question: The sky appears dark to passengers flying at very high altitudes mainly because :
(a) Scattering of light is not enough at such heights.
(b) There is no atmosphere at great heights.
(c) The size of molecules is smaller than the wavelength of visible light.
(d) The light gets scattered towards the earth.

A

Question: If a person can see a doll at the far distance, but he cannot have the newspaper in his hands. What lens should he wear to make correct his eyesight ?
(a) Convex lens
(b) Concave lens
(c) Bi- focal lens
(d) Prism

B

Question: In the following diagram the correctly marked angles are :

(a) ∠A and ∠e
(b) ∠i, ∠A and ∠D
(c) ∠A, ∠i and ∠e
(d) ∠A, ∠r and ∠D

A

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

B

Question: The image formed by the retina of the human eye is :
(a) Virtual and erect
(b) Real and inverted
(c) Virtual and inverted
(d) Real and erect

B

Question: The phenomena of light responsible for the working of the human eye is :
(a) Reflection
(b) Refraction
(c) Power of accommodation
(d) Persistence of vision

B

Question: The light-sensitive cell present on the retina and is sensitive to the intensity of light is :
(a) Cones
(b) Rods
(c) Both rods and cones
(d) None of these

B

Question: Study the following diagram and select the option having correctly marked angles

(a) ∠i, ∠A, ∠D
(b) ∠i, ∠r, ∠D
(c) ∠i, ∠e, ∠A
(d) ∠r, ∠e, ∠D

A

Question: The time difference between actual sunset and the apparent sunset is about
(a) 2 min
(b) 3 min
(c) 4 min
(d) 5 min

A

Question: Dispersion of light by glass prism takes place because
(a) the lights of different colours have different intensities.
(b) the lights of different colours have different speed in a medium.
(c) different colours have different frequencies.
(d) the lights of different colours have different energies.

B

Question: The sky would appear red instead of blue if
(a) atmospheric particles scatter blue light more than red light
(b) atmospheric particles scatter all colours equally
(c) atmospheric particles scatter red light more than blue light
(d) the Sun was much hotter

C

Question: The blue colour of the sky is due to the phenomenon of
(a) scattering
(b) dispersion
(c) internal reflection
(d) atmospheric refraction

A

Question: We can see a rainbow on a sunny day when you look at the sky through a waterfall or through a water fountain
(a) with the Sun in front of you
(b) with the Sun behind you
(d) just after the sunset

B

Question: The colour of light which is deviated the most by a prism in the spectrum of white light is
(a) red
(b) green
(c) violet
(d) yellow

C

Question: At noon the Sun appears white because
(a) light is least scattered
(b) all colours get scattered equally
(c) blue colour is scattered the most
(d) red colour is scattered the most

A

Question: The colour of light which is deviated the least by a prism in the spectrum of white light is
(a) red
(b) green
(c) violet
(d) yellow

A

Question:. Which of the following phenomena of light are involved in the formation of a rainbow?
(a) Reflection, refraction and dispersion
(b) Refraction, dispersion and total internal reflection
(c) Refraction, dispersion and internal reflection
(d) Dispersion, scattering and total internal reflection

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 the other colours by the atmosphere.
(d) light of all other colours is scattered more than the violet and blue colour lights by theatmosphere.

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

B

Question: Which of the following statements is correct regarding the propagation of light of differentcolours of white light in air?
(a) Red light moves fastest.
(b) Blue light travels faster than green light.
(c) All colours of white light move with the same speed.
(d) Yellow light moves with the mean speed as that of red and violet lights.

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

D

Question: The star appear shifted from their actual position due to the phenomenon of:
(a) Diffraction of light
(b) Scattering of light
(c) Refraction of light
(d) Reflection of light

C

Question: Which of the following figures correctly represents the passage of white light through prism?

A

Question: Four students studied refractive of light through a glass prism. They traced the ray of light and measured the angle of incidence ∠i and angle of deviation ∠D as shown in figure A, B, C and D. Which one is the correct representation.

A

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

C

Question: In which of the following cases will no dispersion take place when sunlight passes through it?

B

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

A

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

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

D

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

A

Question: 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

D

Question: The deflection of light by minute particles and molecules of the atmosphere in all direction is called ____________ of light.
(a) dispersion
(b) scattering
(c) interference
(d) tyndell effect

B

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.

B

Question. Which of the following changes occur when you walk out of bright sunshine into a poorly lit room ?
(a) the pupil becomes larger
(b) the lens becomes thicker
(c) the ciliary muscle relaxes
(d) the pupil becomes smaller

A

Question. The defect of vision which cannot be corrected by using spectacles is :
(a) myopia
(b) presbyopia
(c) cataract
(d) hypermetropia

C

Question. A beam of white light falls on a glass prism. The colour of light which undergoes the least bending on passing through the glass prism is :
(a) violet
(b) red
(c) green
(d) blue

B

Question. The colour of white light which suffers the maximum bending (or maximum refraction) on passing through a glass prism is :
(a) yellow
(b) orange
(c) red
(d) violet

D

Question. The blue colour of sky is due to :
(a) refraction of light
(b) dispersion of light
(c) diffraction of light
(d) scattering of light

D

Question. The red colour of the sun at the time of sunrise and sunset is because :
(a) red colour is least scattered
(b) blue colour is least scattered
(c) red colour is most scattered
(d) blue colour is most scattered

D

Question. Which of the following is not caused by the atmospheric refraction of light ?
(a) twinkling of stars at night
(b) sun appearing higher in the sky than it actually is
(c) sun becoming visible two minutes before actual sunrise
(d) sun appearing red at sunset

D

Question. The stars appear higher in the sky than they actually are, due to :
(a) diffraction of light
(b) scattering of light
(c) refraction of light
(d) reflection of light

C

Question. The stars twinkle but the planets do not twinkle at night because :
(a) the stars are small but the planets are large
(b) the stars are very large but planets are small
(c) the stars are much nearer but planets are far off
(d) the stars are far off but planets are nearer to earth

D

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

D

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

C

Question. Due to atmospheric refraction of sunlight, the time from sunrise to sunset is lengthened by about :
(a) 6 minutes
(b) 2 minutes
(c) 4 minutes
(d) 5 minutes

C

Question. The day is longer on the earth by about 4 minutes because :
(a) the earth is round in shape
(b) the earth rotates on its axis
(c) the earth revolves around the sun
(d) the earth has atmosphere

D

Question. How does the eye change in order to focus on near or distant objects ?
(a) The lens moves in or out
(b) The retina moves in or out
(c) The lens becomes thicker or thinner
(d) The pupil gets larger or smaller

C

Question. A young man has to hold a book at arm’s length to be able to read it clearly. The defect of vision is :
(a) astigmatism
(b) myopia
(c) presbyopia
(d) hypermetropia

D

Fill in the following blanks with suitable words :

Question. A short-sighted person cannot see ………… objects clearly.

distant

Question. When a ray of light enters a prism, it bends ………….. the normal.

towards,

Question. The blue colour of sky is due to …………… of light.

scattering.

Question Most of the refraction of light rays entering the eye occurs at the outer surface of the………….

cornea

Question. The part of eye sensitive to light is……………….

retina

Question. The part of eye which alters the size of the pupil is……………

iris

Question. When light is dim, the pupil becomes…………….

large

Question. The iris controls the amount of……………….entering the eye.

light

Question. The ciliary muscles control the shape of the …………….

eye-lens

Question. To bring light from a distant object to a focus on the retina of the eye, the convex eye-lens needs to be made……….

thinner

Question. To bring light from a near object to a focus on the retina of the eye, the convex eye-lens needs to be made…….

thicker

Question. Name the defect of vision in which the eye-lens loses its power of accommodation due to old age.

Presbyopia

Question. What is the other name of old age hypermetropia ?

Presbyopia

Question. Name one defect of vision (or eye) which cannot be corrected by any type of spectacle lenses.

Cataract

Question. Name the body part with which the terms myopia and hypermetropia are connected.

Eye

Question. Name the part of the retina which is insensitive to light.

Blind spot

Question. Which part of the eye contains cells which are sensitive to light ?

Retina

Question. Name the part of our eyes which helps us to focus near and distant objects in quick succession.

Ciliary muscles

Question. Name two parts of the eye which refract light rays (or bend light rays).

Cornea and Eye-lens

State whether the following statements are true or false :

Question. The scattering away of red light makes the sky appear blue during the day time.

False

Question. The scattering away of blue light makes the sun appear red at sunset.

True

Question. Rabbit has eyes which look sideways.

True

Question. Short-sightedness can be cured by using a concave lens.

True

Question. The image formed on our retina is upside-down

True

Assertion and Reasoning Based Questions

Directions : In the following questions, a statement of assertion is followed by a statement of reason. Mark the correct choice as :
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true, but reason is not the correct explanation of assertion.
(c) If assertion is true, but reason is false.
(d) If assertion is false but reason is true.

Question. Assertion : The human eye is one of the most valuable and sensitive sense organs.
Reason : Eye enables us to see the wonderful world and the colours around us.
Answer : (a) We know that human eye is the most valuable sense organ because it enables us to see this colourful world. Thus, the given reason is correct explanation of the assertion.

Question. Assertion : Hypermetropia is also known as nearsightedness.
Reason : The image of a distant object is not formed in front of the iris.
Answer : (d) Myopia is known as near-sightedness and hypermetropia is known as farsightedness. The image of a distant object is not formed in front of the iris instead it is formed in front of retina. Thus, the given assertion and reason are false.

Question. Assertion : The curvature of the eye lens can be modified to some extent by the ciliary muscles.
Reason : The ciliary muscles are used to modify the curvature of lens.
Answer : (a) The curvature of the eye lens is modified to change the focal length. When the muscles are relaxed, the lens becomes thin. Therefore, there is an increase in the focal length. This enables us to see distant objects clearly. This modification in lens is done by ciliary muscles. Thus, both assertion and reason are true and reason is the correct explanation of assertion.

Question. Assertion : The Sun appears red during sunrise or sunset.
Reason : The scattering of light is inversely proportional to its wavelength.
Answer : (a) We can see the sun and its surroundings appear red colour during both sunrise and sunset. It happens due to the scattering of light is inversely proportional to the fourth power of its wavelength. Thus, both assertion and reason are true and reason is the correct explanation of assertion.

Question. Assertion : Sometimes, the eye may gradually lose its power of accommodation.
Reason : The crystalline lens of people at old age becomes milky and cloudy.
Answer : (b) The person cannot see the objects distinctly and comfortably because of accommodation. The vision becomes blurred due to the refractive defects of the eye. Therefore, the given assertion is true, but reason is not the correct explanation of assertion.

Creating Based Questions

Question. What would be your suggestion to your grandfather who is undergoing the eye defects both hypermetropia and myopia ?
Myopia is the near-sightedness and hypermetropia is the far-sightedness. The person who is suffering from both eye defects is advised to wear spectacles with a bi-focal lens which consists of both concave and convex lens. The upper portion would be a concave lens which rectifies the distant vision and lower portion is a convex lens which rectifies the near vision.

Question. Reena was diagnosed with a short-sight problem. She was advised to wear spectacles continuously which made her feel low about her beauty. What would you suggest Reena other than wearing spectacles ?
Answer : When Reena is diagnosed with short-sight problem, the better advice to be considered is that she can wear spectacles. But when she is not comfortable wearing spectacles, I would suggest her to fix lens which won’t degrade her looks and will make her feel confident.

Question. In today’s digital world, every human spends around a minimum eight hours with the digital electronic items which make their eyes to strain more and causes many eye problems. Still they undergo many exercises for their eyes during their working hours what would be your medical suggestion to reduce the stress and strain caused in the eyes ?
Answer : In addition to the exercise for the strained eyes, my medical suggestion would be the usage of the anti-glare lens in their spectacles which reduces the impact of blue light emitted from digital items and artificial lighting. This would reduce the stress and strain caused. But still the exercise for eyes in repeated time interval should also be regularly followed.

Question. Babin was diagnosed with a long sight problem. He was advised to wear lens but he was worried that wearing lens should be given an utmost care in his busy schedule. What would you suggest Babin other than usage of lens ?
Answer : It was a big problem for Babin to take care of lens in his busy schedule due to this reason I suggested him to undergo laser operation which would correct all common vision problems like near sight, a long sight which reduce the dependency on the lens. The eye treatment using laser is safe and effective.

Question. John has undergone all medication including wearing spectacles, lens and laser treatment. None of the treatment helped him to recover his eyesight. What would be your suggestion to overcome his problem in his eyesight ?
Answer : Though all the treatment for recovering from his eye problems did not help him out, I would suggest him to opt for eye transplantation which would get his eyesight back to normal. In transplantation of eye, the entire diseased eye cannot be replaced. Only the diseased cornea can be replaced by the donated cornea.

Paragraph/Table and Case Study Based Questions

1. Read the following and answer any four questions from 1(i) to 1(v):
The ciliary muscles of eye control the curvature of the lens in the eye and hence can alter the effective focal length of the system. When the muscles are fully relaxed, the focal length is maximum, when muscles are strained the curvature of lens increases (that means radius of curvature decreases) and focal length decreases. For a clear vision the image must be on retina. The image distance is therefore fixed for clear vision and it equals the distance of retina from eye lens. It is about 2.5 cm for a grown person.
A person can theoretically have clear vision of objects situated at any large distance from the eye. The smallest distance at which a person can clearly see is related to the minimum possible focal length. The ciliary muscles are most strained in this position. For an average grown-up person minimum distance of object should be around 25 cm.
A person suffering for eye defects uses spectacles (eye glass). The function of lens of spectacles is to form the image of the objects within the range in which person can see clearly. The image of the spectacle lens becomes object for eye lens and whose image is formed on retina.

The number of spectacle lens is equal to the numerical value of the power of lens with sign. For example, power of lens required is + 3D (converging lens of focal length 100/3 cm) then number of lens will be + 3.

Question. Match the following columns:

(a) I-q, II-r, III-s, IV-t, V-p
(b) I-r, II-q, III-s, IV-t, V-p
(c) I-p, II-q, III-r, IV-s, V-t
(d) I-p, II-r, III-q, IV-s, V-t

A

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

B

Question. The focal length of the eye increases when eye muscles:
(a) are relaxed and lens becomes thinner
(b) contract and lens becomes thicker
(c) are relaxed and lens becomes thicker
(d) contract and lens becomes thinner

A

Question. The near point of a hypermetropic eye is at 75cm from the eye, what is the power of the lens required to enable him to read clearly a book held at 25cm from the eye?
(a) 2.00D
(b) 3.00D
(c) 3.75D
(d) 2.66D

D

Question. A person cannot see the objects distinctly, when placed at a distance less than 100cm, what is the power of the spectacles that he should use to see clearly the objects placed at 25cm?
(a) 2.0D
(b) 3.0D
(c) 2.75D
(d) 3.75D

B

2. White light is a mixture of seven colours is violet, indigo, blue, green, yellow, orange and red. Every colour has its own characteristic wavelength. Different colours with their wavelengths are given below is the table.

The phenomeon of splitting white light into seven colors when it passes through a glass prism is called dispersion of white light.

Question. Name the phenomenon occurring in nature due to dispersion of light.
(i) Twinkling of stars
(ii) Rainbow
(iii) delayed sunrise
(iv) Red Sunrise

B

Question. Light of two colours A and B pass through a glass prism. ‘A’ deviates more than B from its path of incidence. Which colour has a higher speed in the prism ?
(i) color A has higher speed than that of color B
(ii) Color B has higher speed than that of color A
(iii) both have same speed
(iv) None of the above

B

Question. Choose the correct option.
(i) Each colour of light travels with same speeds in a given medium.
(ii) Each colour of light travels with different speeds in a given medium.
(iii) Only red colour of light travels with fast speed in a given medium.
(iv) all of the above.