1) A girl 1.8 m tall is standing 2.8 m in front of a camera which is using a convex lens having a focal length of 0.04 m. The image is a. not formed b. real c. virtual d. fake image
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2) If the object is towards the left side of the lens, the object distance will be a. zero b. constant c. positive d. negative
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3) The relation between the object and image distance from the lens in terms of the focal length of the lens is called a. fiber optics b. lens formula c. ohm's law d. optical law
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4) The entire light is reflected into the denser medium, which is called total a. internal reflection of light b. external reflection of light c. internal refraction of light d. external refraction of light
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5) The relationship between object distance (p), image distance (q) from the mirror and focal length (f) of the mirror is known as a. glass formula b. mirror formula c. speed formula d. energy formula
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6) The distance between the optical center and principal focus is a. radius b. focal length c. linear length d. 2 focal lengths
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7) If fo is the focal length of the objective and fe is the focal length of the eyepiece, then magnification of a refracting (M) telescope can be determined as a. M = fo/fe b. M = fo + fe c. M = fo - fe d. M = fe/fo
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8) The mirror formula is a. 1⁄f + 1⁄p + 1⁄q b. 1⁄f = 1⁄p + 1⁄q c. 1⁄p + 1⁄q d. 1⁄p = 1⁄f x 1⁄q
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9) If a concave lens has a focal length of 15 cm and image distance is 10 cm then object distance is a. 30 cm b. 50 cm c. 40 cm d. 60 cm
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10) One side of the spherical mirror is opaque and the other side is a. non reflecting b. translucent c. transparent d. reflecting
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11) A telescope that uses two converging lenses is called a. reflecting telescope b. refracting telescope c. simple telescope d. compound microscope
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12) A convex lens of focal length 8 cm is to be used to form a virtual image 2 times the size of the object. Where must the lens be placed? a. 3 cm b. 4 cm c. 5 cm d. 8 cm
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13) The core is made of glass or plastic of relatively a. zero refractive index b. high refractive index c. low refractive index d. no refractive index
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14) The minimum distance of an object from the eye at which it produces a sharp image on the retina is known as a. accommodation b. near point c. far point d. hypermetropia
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15) The size of the image depends on the position of the object in a. plane mirror b. convex mirror c. concave mirror d. silver mirror
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16) If an object is 14 cm in front of the convex mirror and image distance is 5.8 cm then it's focal length is a. -20 cm b. -4.1cm c. -9.9 cm d. -8.2 cm
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17) Rough surfaces reflect rays of light in a. two directions b. one direction c. many directions d. no direction
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18) Speed of light in air/speed of light in a medium is equal to the index of a. defraction b. acoustics c. reflection d. refraction
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19) A magnifying glass is also called a. telescope b. compound microscope c. simple microscope d. endoscope
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20) The critical angle for glass is a. 50 ° b. 42 ° c. 45 ° d. 30 °
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