--- title: "The Human Eye and the Colourful World: CBSE Class 10 Science previous year questions" url: https://www.swavid.com/cbse/class-10/science/pyq/the-human-eye-and-the-colourful-world --- # The Human Eye and the Colourful World: CBSE Class 10 Science previous year questions 10 questions from CBSE Class 10 board papers, newest first, each with full working. ## CBSE Class 10 Science Question Paper 2026 (Set 31/1/1) with Solutions ### Question 31 *1 mark · MCQ* When you look at an object very close to your eyes, the : - Ciliary muscles of your eye contract and the eye lens becomes thick. - Ciliary muscles of your eye get relaxed and the eye lens becomes thick. - Ciliary muscles of your eye contract and the eye lens becomes thin. - Ciliary muscles of your eye get relaxed and the eye lens becomes thin. **Solution** 1. When an object is placed very close to the eyes, the ciliary muscles contract to increase the curvature of the eye lens. 2. This makes the eye lens thicker so that its focal length decreases to focus the image on the retina. 3. Therefore, the correct option is (a). **Answer:** (a) Ciliary muscles of your eye contract and the eye lens becomes thick. > Common mistake: Confusing the action of ciliary muscles for near and distant vision. ### Question 32 *1 mark · Assertion and reason* Assertion (A) : When rays of white light pass through a prism, on emerging they give spectrum of seven colours. Reason (R) : It is due to the scattering of light that red light bends minimum and violet light bends the maximum. - Both, Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A). - Both, Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A). - Assertion (A) is true, but Reason (R) is false. - Assertion (A) is false, but Reason (R) is true. **Solution** 1. Assertion (A) is true because white light splits into its seven constituent colours when passing through a glass prism. 2. Reason (R) is false because the spectrum is due to refraction and dispersion (different colours bending at different angles), not scattering of light. 3. Therefore, Assertion (A) is true, but Reason (R) is false. **Answer:** Assertion (A) is true, but Reason (R) is false. > Common mistake: Mistaking dispersion and refraction through a prism for atmospheric scattering of light. ### Question 35 *3 marks · Short answer* A person is unable to read a book placed closer than $1\text{ meter}$ from his eyes. Identify the defect of vision in his eyes. Draw the ray diagrams to show the defect of vision and its correction. **Solution** 1. The defect of vision is Hypermetropia or farsightedness. 2. Diagram: Draw a convex lens of the eye with the image forming behind the retina. 3. Diagram: Draw a convex lens placed in front of the eye to converge light rays onto the retina. **Answer:** The defect is Hypermetropia. > Common mistake: Confusing Hypermetropia with Myopia and drawing the wrong lens for correction. ## CBSE Class 10 Science Question Paper 2025 (Set 31/1/1) with Solutions ### Question 14 *1 mark · MCQ* An old person is suffering from an eye defect caused by weakening of ciliary muscles and diminishing flexibility of the eye lens. If the defect of vision is 'a' which can be corrected by lens 'b', then 'a' and 'b' respectively are : - hypermetropia and convex lens - presbyopia and bifocal lens - myopia and concave lens - myopia and bifocal lens **Solution** 1. The weakening of ciliary muscles and diminishing flexibility of the eye lens in old age leads to the defect of vision known as presbyopia. 2. Presbyopia is corrected using a bifocal lens consisting of both concave and convex lenses. **Answer:** (b) presbyopia and bifocal lens > Common mistake: Confusing presbyopia with hypermetropia or myopia. ## CBSE Class 10 Science Question Paper 2024 (Set 31/1/1) with Solutions ### Question 13 *1 mark · MCQ* The lens system of human eye forms an image on a light sensitive screen, which is called as : - Cornea - Ciliary muscles - Optic nerves - Retina **Solution** 1. The human eye uses a lens system to form an image on a light-sensitive screen called the retina. **Answer:** (d) Retina > Common mistake: Confusing the cornea with the retina as the screen for image formation. ### Question 20 *1 mark · Assertion and reason* Assertion (A) : The rainbow is a natural spectrum of sunlight in the sky. Reason (R) : Rainbow is formed in the sky when the sun is overhead and water droplets are also present in air. - Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A). - Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A). - Assertion (A) is true, but Reason (R) is false. - Assertion (A) is false, but Reason (R) is true. **Solution** 1. A rainbow is a natural spectrum of sunlight appearing in the sky, caused by dispersion of sunlight by tiny water droplets present in the atmosphere. 2. The Assertion (A) is true. 3. Rainbows are observed when the sun is behind the observer and water droplets are in front, not when the sun is overhead. 4. Therefore, the Reason (R) is false. **Answer:** Assertion (A) is true, but Reason (R) is false. > Common mistake: Students often assume both statements are true because both mention rainbows and water droplets. ### Question 31 *3 marks · Short answer* Study the diagram given below and answer the questions that follow : (i) Name the defect of vision represented in the diagram. Give reason for your answer. (ii) List two causes of this defect. (iii) With the help of a diagram show how this defect of vision is corrected. **Part (i)** 1. The defect shown is myopia (near-sightedness). 2. Reason: The rays are converging in front of the retina instead of on the retina. Answer (i): Myopia; rays converge in front of the retina. **Part (ii)** 1. Excessive curvature of the eye lens. 2. Elongation of the eyeball. Answer (ii): 1. Excessive curvature of eye lens. 2. Elongation of the eyeball. **Part (iii)** 1. This defect is corrected by using a concave lens of suitable power. 2. Diagram: A concave lens placed in front of the eye diverges the incoming rays so that they focus on the retina. Answer (iii): Corrected using a suitable concave lens. **Answer:** The defect is myopia, caused by excessive curvature of the eye lens or elongation of the eyeball, and is corrected using a concave lens. > Common mistake: Confusing myopia with hypermetropia and recommending a convex lens for correction. ## CBSE Class 10 Science Question Paper 2023 (Set 31/1/1) with Solutions ### Question 25 *2 marks · Very short answer* (a) A narrow beam XY of white light is passing through a glass prism ABC as shown in the diagram : [Diagram of white light passing through prism] Trace it on your answer sheet and show the path of the emergent beam as observed on the screen PQ. Name the phenomenon observed and state its cause. **Solution** 1. Draw the prism ABC and the incident white beam XY refracting towards the base, splitting into a band of seven colours (VIBGYOR) with violet bending the most and red the least, and striking the screen PQ. 2. The phenomenon observed is dispersion of white light, caused by the bending of light rays of different wavelengths through different angles by the glass prism. **Answer:** Dispersion of white light; caused by different angles of bending for different colours. > Common mistake: Reversing the bending order of red and violet colours. ### Question 25 (OR) *2 marks · Very short answer* (b) It is observed that the power of an eye to see nearby objects as well as far off objects diminishes with age. (i) Give reason for the above statement. (ii) Name the defect that is likely to arise in the eyes in such a condition. (iii) Draw a labelled ray diagram to show the type of corrective lens used for restoring the vision of such an eye. **Part (i)** 1. It is caused by the gradual weakening of the ciliary muscles and diminishing flexibility of the eye lens with age. Answer (i): Weakening of ciliary muscles and loss of flexibility of the eye lens. **Part (ii)** 1. The defect of vision is called presbyopia. Answer (ii): Presbyopia **Part (iii)** 1. Diagram: Draw a bifocal lens showing both the upper concave part for distant vision and the lower convex part for near vision. Answer (iii): Corrective lens: Bifocal lens. **Answer:** Presbyopia is caused by the gradual weakening of ciliary muscles and diminishing flexibility of the eye lens, corrected using a bifocal lens. > Common mistake: Confusing presbyopia with simple myopia or hypermetropia. ### Question 31 *3 marks · Short answer* Give reasons for the following : (a) Danger signals installed at airports and at the top of tall buildings are of red colour. (b) The sky appears dark to the passengers flying at very high altitudes. (c) The path of a beam of light passing through a colloidal solution is visible. **Part (a)** 1. Red colour has the longest wavelength among visible colours and is least scattered by fog or smoke, so it can be seen over long distances. Answer (a): Red light is least scattered by fog or smoke. **Part (b)** 1. At very high altitudes, there is no atmosphere containing particles to scatter sunlight, hence the sky appears dark. Answer (b): Due to the absence of atmosphere and scattering at high altitudes. **Part (c)** 1. Colloidal particles are large enough to scatter a beam of light passing through them, making the path of light visible (Tyndall effect). Answer (c): Due to scattering of light by colloidal particles (Tyndall effect). **Answer:** (a) Red light is least scattered, (b) absence of atmosphere for scattering, (c) scattering of light by colloidal particles (Tyndall effect). > Common mistake: Writing that red light is scattered most instead of least. ## Related pages - [The Human Eye and the Colourful World: NCERT solutions](https://www.swavid.com/science/class/10/chapter/the-human-eye-and-the-colourful-world/ncert-solutions) - [All CBSE Class 10 Science papers](https://www.swavid.com/cbse/class-10/science/previous-year-papers) Solutions written by SwaVid, a personal AI tutor for Class 6 to 10 Maths and Science. Practise this chapter free: https://www.swavid.com/start/student