| 1. | What is the relation between focal length (f) and radius of curvature (r) of a curve mirror ? | |
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f = 3r/2
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f = r/3
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f = 2r
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f = r/2
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Report Question| 2. | A concave mirror forms a real and enlarged image of an object if the object is placed at/between ? | |
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F and P
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F
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2F
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F and C
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| 3. | In torches, search lights and headlights of vehicles the bulb is placed ? | |
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at the centre of curvature of the reflector
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between the focus and centre of curvature of the reflector
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between the pole and the focus of the reflector
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very near to the focus of the reflector
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| 4. | A child is standing in front of a magic mirror. She finds the image of her head bigger, the middle portion of her body of the same size and that of the legs smaller. The following is the order of combinations for the magic mirror from the top ? | |
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Convex, plane and concave
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Convex, concave and plane
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Plane, convex and concave
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Concave, plane and convex
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| 5. | A ray of light strikes the surface of mirror at an angle of 300 with the mirror. The angle of reflection is ? | |
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450
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700
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600
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300
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| 6. | A point source of light is placed at the centre of curvature of a concave mirror. The angle of deviation of the rays incident on the mirror from this source and reflected from it is ? | |
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360 degrees
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90 degrees
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180 degrees
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0
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| 7. | A point object is placed at a distance of 20 cm from a convex mirror of focal length 20 cm. The image will form at ? | |
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behind the mirror
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at the pole
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at focus
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at infinity
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| 8. | A divergent lens will produce ? | |
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always real image
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both real and virtual image
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none of these
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always virtual image
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| 9. | The refractive index of transparent medium is greater than one because ? | |
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Frequency of light wave changes when it moves from rarer to denser medium
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Speed flight in vacuum = speed of light in transparent medium
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Speed of light in vacuum > speed of light in transparent medium
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Speed of light in vacuum < speed of light in transparent medium
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| 10. | You are given three medium A, B and C of refractive index 1.33, 1.65 and 1.46. The medium in which the light will travel fastest is ? | |
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equal in all three medium
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C
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B
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A
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