1) In the human eye, pictures are recorded by a. cornea b. pupil c. retina d. iris
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2) An object 4 cm high is placed at a distance of 12 cm from a concave lens, If the focal length is 8 cm then the position of the object is a. 20 cm b. 25 cm c. 24 cm d. 22 cm
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3) A spherical mirror whose outer curved surface is reflecting is called a. convex mirror b. concave mirror c. lens d. plane mirror
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4) The center of a sphere of the spherical mirror is called a. radius of curvature b. pole c. center of curvature d. focal length
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5) The lens which is thick at the center but thin at the edges is called a. counter lens b. fiber lens c. convex lens d. concave lens
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6) The radius of the sphere of which spherical mirror is a part is known as a. radius of curvature b. pole c. center of curvature d. focal length
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7) The incident ray, the normal and the refracted ray at the point of incidence all lie in the same plane. This is the law of a. reflection b. refraction c. defraction d. acoustics
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8) As the focal length of a convex lens is positive, therefore its power should be a. always zero b. also positive c. negative d. none of above
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9) A lens which converges the incident rays on a single point is a. convex lens b. concave lens c. biconcave lens d. bioconvex lens
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10) The condition in which the image is formed behind the retina is called a. Farsightedness b. Nearsightedness c. image defect d. blind spotting
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11) The short-sightedness can be corrected if a. converging glasses are used b. converging mirror is used c. diverging mirror is used d. diverging glasses is used
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12) The endoscope used to examine the stomach is called a. cystoscope b. gastroscope c. microscope d. bronchoscope
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13) An object 20 cm tall is located 14 cm from a concave mirror having focal length 20 cm. The image is located at a. 30 cm b. 46.7 cm c. 35.6 cm d. 32.5 cm
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14) The distance from the pole to the principal focus measured along the a. center of curvature b. principal axis c. vertex d. radius of curvature
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15) In the fiber-optic thread, the refractive index of the inner core is a. less than cladding b. equal to cladding c. higher than cladding d. all of above
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16) The line joining the center of curvature and pole of the spherical mirror is known as a. center of curvature b. focal length c. principal axis d. vertex
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17) Some people can not see distant objects clearly without spectacles. This defect is called a. accommodation b. stress c. farsightedness d. nearsightedness
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18) The focal length is positive for a. diverging lens b. converging lens c. biconcave lens d. convex lens
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19) The refractive index of a medium is a. Speed of light in air to speed of light in vacuum b. Speed of light in vacuum to speed of light in air c. focal length to object distance d. speed of light in the medium x speed of light in the air
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20) Only virtual and erect images can be formed by a a. convex mirror b. concave mirror c. silver mirror d. plane mirror
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