CBSE Class 10 Science Chapter-11 Human Eye and Colourful World – Free PDF Download
Free PDF download of Important Questions with Answers for CBSE Class 10 Science Chapter 11 – Human Eye and Colourful World prepared by expert Science teachers from latest edition of CBSE(NCERT) books only by CoolGyan to score more marks in CBSE board examination.
CBSE Class 10 Science Chapter-11 Human Eye and Colourful World Important Questions
CBSE Class 10 science Important Questions Chapter 11 – Human Eye and Colourful World
1 Mark Questions
1. 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
Ans. (b) Only nearby objects
2. The defect of myopia can be corrected by using
(a) Concave lens
(b) Convex lens
(c) Either concave or convex
(d) A complicated combination of lenses.
Ans. (a) Concave lens
3. The colour that is scattered the least by the tiny particles and the atoms/ molecules of the atmosphere is
(a) Violet
(b) Green
(c) yellow
(d) Red
Ans. (d) Red
4. 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
Ans. (b) Scattering of light
5. The focal length of the eye lens 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.
Ans. (a) are relaxed and lens becomes thinner
6. Define power of accommodation?
Ans. The ability of the eye lens to adjust its focal length is called power of accommodation.
7. Which part of the human eye provides most of the refraction for the light rays entering the eye?
Ans. Cornea and Aqueous humour
8. What happens to the image distance in the eye when we increase the distance of an object from the eye?
Ans. It remains the same
9. What happens to the pupil of the eye when the light is very bright?
Ans. Size of the pupil becomes small.
10. Which part of the human eye conveys the electrical signals generated by the light sensitive cells of the retina, on the brain?
Ans. Optic nerves
11. 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
Ans. (b) Accommodation
12. The human eye forms the image of an object at its
(a) Cornea
(b) Iris
(c) Pupil
(d) Retina
Ans. (d) Retina
13. 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
Ans. (c) 25 cm
14. The change in focal length of an eye lens is caused by the action of the
(a) Pupil
(b) Retina
(c) Cilliary muscles
(d) Iris
Ans. (c) Cilliary muscles
15. What would have been the colour of the sky if there had not been any atmosphere around the earth?
Ans. black.
16. For dispersion of light through a prism which colour has maximum deviation?
Ans. violet
17. What is the least distance of distinct vision of a normal human eye?
Ans. 25cm.
18. Name the muscle responsible for bringing change in the focal length of the eye lens?
Ans. Ciliary muscle.
19. Name one defect of vision which cannot be corrected by any type of spectacle lenses?
Ans. Cataract.
20. State one effect produced by the scattering of light by the atmosphere?
Ans. Tyndall effect.
21. What is the nature of image formed on the retina of the eye?
Ans. Real and inverted.
22. What type of lens is used for correcting hypermetropia?
Ans. Convex lens.
23. Who was the first person to obtain the spectrum of sunlight?
Ans. Sir Isaac Newton.
24. As light rays pass from air into glass prism, are they refracted towards or away from the normal?
Ans. Towards the normal.
25. Which color has largest wavelength?
Ans. Red color. Ant
26. Which defect of vision can be rectified using a concave lens?
Ans. Myopia.
27. What phenomenon causes twinkling of star on a clear night?
Ans. Atmospheric refraction.
28. What is meant by scattering of light?
Ans. Change of direction of light on striking a scattered.