10. The Human Eye and the Colourful World

*नोट: यह सेक्शन रिवीजन के लिए है। अपना ज्ञान परखने के लिए ऊपर दिए गए क्विज़ में भाग लें।

1. The ability of the eye lens to adjust its focal length is called:
   A) Near-sightedness  |  B) Accommodation  |  C) Far-sightedness  |  D) Presbyopia
2. The least distance of distinct vision for a normal eye is:
   A) 25 meters  |  B) 25 centimeters  |  C) Infinite  |  D) 1 meter
3. Where is the image of an object formed in the human eye?
   A) Cornea  |  B) Iris  |  C) Retina  |  D) Pupil
4. Which part of the eye controls the amount of light entering it?
   A) Retina  |  B) Pupil  |  C) Cornea  |  D) Lens
5. Which phenomenon of light is mainly responsible for the formation of a rainbow?
   A) Only reflection  |  B) Dispersion  |  C) Only refraction  |  D) None of these
6. Twinkling of stars is due to:
   A) Reflection  |  B) Atmospheric Refraction  |  C) Dispersion  |  D) Scattering
7. The blue color of the sky is due to:
   A) Refraction  |  B) Scattering of light  |  C) Reflection  |  D) Dispersion
8. Which lens is used to correct Myopia (Near-sightedness)?
   A) Convex lens  |  B) Concave lens  |  C) Cylindrical  |  D) Plane
9. Which lens is used to correct Hypermetropia (Far-sightedness)?
   A) Concave  |  B) Convex lens  |  C) Bifocal  |  D) None of these
10. Who controls the size of the pupil in the human eye?
    A) Ciliary muscles  |  B) Iris  |  C) Retina  |  D) Cornea
11. Splitting of white light into seven colors is called:
    A) Refraction  |  B) Dispersion  |  C) Reflection  |  D) Scattering
12. In the spectrum of white light, which color bends the most?
    A) Red  |  B) Violet  |  C) Yellow  |  D) Green
13. In the spectrum, which color bends the least?
    A) Blue  |  B) Red  |  C) Violet  |  D) Orange
14. Which part of the eye is donated during eye donation?
    A) Retina  |  B) Cornea  |  C) Lens  |  D) Whole eye
15. Why is the color of danger signals red?
    A) For beauty  |  B) Red light is scattered the least  |  C) It looks sharp  |  D) None of these
16. How does the sky appear to passengers flying at very high altitudes?
    A) Blue  |  B) Black  |  C) White  |  D) Red
17. How many triangular bases does a glass prism have?
    A) One  |  B) Two  |  C) Three  |  D) Five
18. Who changes the focal length of the eye lens?
    A) Pupil  |  B) Ciliary muscles  |  C) Iris  |  D) Optic nerve
19. What is used to correct Presbyopia?
    A) Concave  |  B) Convex  |  C) Bi-focal lens  |  D) None of these
20. The bending of a ray of light towards the base when passing through a prism is:
    A) Reflection  |  B) Deviation  |  C) Scattering  |  D) None of these
21. Why does the sun appear reddish at sunrise?
    A) Due to refraction  |  B) Scattering of blue light (red remains)  |  C) Due to reflection  |  D) Due to dust
22. Tyndall Effect is based on which phenomenon of light?
    A) Refraction  |  B) Scattering  |  C) Reflection  |  D) Dispersion
23. The reason for the blue color of the clear sky is:
    A) Fine particles in air scatter blue light  |  B) Sea water  |  C) Clouds  |  D) Oxygen
24. What is the nature of the image formed on the retina?
    A) Erect and virtual  |  B) Inverted and real  |  C) Large and erect  |  D) None of these
25. In the dispersion of white light by a prism, which color has the longest wavelength?
    A) Violet  |  B) Red  |  C) Green  |  D) Yellow
26. In which defect can a person see near objects clearly but not far objects?
    A) Far-sightedness  |  B) Myopia  |  C) Presbyopia  |  D) Astigmatism
27. Which lens is in the upper part of a bifocal lens?
    A) Convex  |  B) Concave (for distant objects)  |  C) Plane  |  D) Cylindrical
28. Which cells of the retina are sensitive to colors?
    A) Rods  |  B) Cones  |  C) Pupil  |  D) Lens
29. Which group consists of primary colors of light?
    A) Yellow, Blue, Red  |  B) Red, Green, Blue  |  C) White, Black, Brown  |  D) None of these
30. Why do planets not twinkle?
    A) They are cold  |  B) They are closer to Earth and act as extended sources  |  C) They don't have light  |  D) None of these
31. What is the cause of advanced sunrise and delayed sunset?
    A) Atmospheric Refraction  |  B) Dispersion  |  C) Scattering  |  D) Reflection
32. The visibility of the path of light in a colloidal solution is called:
    A) Deviation  |  B) Tyndall effect  |  C) Refraction  |  D) None of these
33. What is the approximate diameter of the eyeball?
    A) 1 cm  |  B) 2.3 cm  |  C) 5 cm  |  D) 10 cm
34. Where does most of the refraction of light rays entering the eye occur?
    A) At the lens  |  B) Outer surface of the cornea  |  C) At the retina  |  D) At the iris
35. In Myopia, where is the image formed?
    A) On the retina  |  B) In front of the retina  |  C) Behind the retina  |  D) At the blind spot
36. In Hypermetropia, where is the image formed?
    A) On the retina  |  B) Behind the retina  |  C) In front of the retina  |  D) On the lens
37. Which molecules in the atmosphere scatter light the most?
    A) CO2  |  B) Nitrogen and Oxygen (fine particles)  |  C) Helium  |  D) Argon
38. What is the Angle of prism?
    A) Angle at the base  |  B) Angle between two lateral faces  |  C) 90 degree angle  |  D) None of these
39. The value of the angle of deviation depends on:
    A) Only color  |  B) Angle of incidence and angle of prism  |  C) Only air  |  D) None of these
40. Which defect arises when the power of accommodation of the eye decreases?
    A) Cataract  |  B) Presbyopia  |  C) Night blindness  |  D) None of these
41. Who first discovered the dispersion of light?
    A) Einstein  |  B) Isaac Newton  |  C) C.V. Raman  |  D) Snell
42. In which direction is a rainbow always formed relative to the sun?
    A) In the direction of the sun  |  B) In the opposite direction to the sun  |  C) Upwards  |  D) Downwards
43. Raman Effect is related to:
    A) Reflection  |  B) Scattering of light  |  C) Refraction  |  D) Polarization
44. What happens to the eye lens in the case of a Cataract?
    A) Becomes transparent  |  B) Becomes milky and cloudy  |  C) Turns red  |  D) Turns blue
45. What is the function of the Optic nerve?
    A) Control light  |  B) Transmit electrical signals to the brain  |  C) Bend the lens  |  D) None of these
46. Where is the blind spot located?
    A) Near the pupil  |  B) Where the optic nerve leaves the retina  |  C) On the cornea  |  D) Middle of the lens
47. How would the sky appear in the absence of an atmosphere?
    A) Blue  |  B) Black (no scattering)  |  C) White  |  D) Yellow
48. The spreading of light in all directions by particles of a medium is called:
    A) Refraction  |  B) Scattering  |  C) Deviation  |  D) Reflection
49. Why does red light deviate the least when passing through a prism?
    A) It's beautiful  |  B) It has the longest wavelength and high velocity  |  C) It's heavy  |  D) None of these
50. Who invented the bifocal lens?
    A) Newton  |  B) Benjamin Franklin  |  C) Thomas Edison  |  D) Galileo
51. Where is 'Vitreous humour' found in the eye?
    A) Between cornea and lens  |  B) Between lens and retina  |  C) Inside the pupil  |  D) None of these
52. Water droplets act as what during rainbow formation?
    A) Lenses  |  B) Tiny prisms  |  C) Mirrors  |  D) None of these
53. Why does the sun appear white at noon?
    A) Sunlight is strong  |  B) Scattering is very little  |  C) Clouds appear  |  D) None of these
54. What is the correct order of colors in the spectrum (bottom to top)?
    A) VIBGYOR  |  B) ROYGBIV  |  C) GYORVIB  |  D) None of these
55. What happens to the size of the pupil in the dark?
    A) Becomes small  |  B) Becomes large (dilates)  |  C) Closes  |  D) Remains same
56. What is the size of the pupil in bright light?
    A) Large  |  B) Small (contracts)  |  C) Same  |  D) None of these
57. What is the time of Persistence of Vision?
    A) 1 second  |  B) 1/16 of a second  |  C) 10 seconds  |  D) 1 minute
58. What is the function of 'Rods' cells in the retina?
    A) Color identification  |  B) Sensitivity to dim light  |  C) Inverting vision  |  D) None of these
59. How much earlier does the sun appear before actual sunrise due to atmospheric refraction?
    A) 10 minutes  |  B) 2 minutes  |  C) 5 minutes  |  D) 30 seconds
60. What is used to prevent scattering in searchlights and headlights bulbs?
    A) Convex mirror  |  B) Concave reflectors  |  C) Lens  |  D) None of these