| 1. | Focal length of a convex lens is 15 cm. For which distance an object is placed so that the lens acts as a magnifying glass ? | |
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Exactly at 30 cm
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Greater than 30 cm
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Less than 15 cm
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Between 15 cm and 30 cm
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Report Question| 2. | A Full-Length Image of a distant tall building can definitely be seen by using ? | |
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A convex mirror
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A concave mirror
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Both concave as well as plane mirror
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A plane mirror
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| 3. | When the object is placed between f and 2f of a convex lens, the image formed is ? | |
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between O and f
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beyond 2f
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at 2f
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at f
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| 4. | When light falls on a smooth polished surface, most of it ? | |
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is refracted into the second medium
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is reflected in the same direction
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is scattered
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is reflected in different directions
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| 5. | A full length image of a distant tall building can definitely be seen by using ? | |
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a convex mirror
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a plane mirror
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both concave as well as plane mirror
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a concave mirror
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| 6. | A light ray enters from medium A to medium B as shown in figure. The refractive index of medium B relative to A will be ? | |
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zero
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equal to unity
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less than unity
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greater than unity
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| 7. | A concave mirror of focal length 20 cm forms an image having twice the size of object. For the virtual position of object, the position of object will be at ? | |
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At infinity
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10 cm
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40 cm
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25 cm
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| 8. | 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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| 9. | A Concave mirror produces magnification of +4. the object is placed ? | |
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Between focus and pole
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Beyond the centre of curvature
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At the focus
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Between focus and centre of curvature
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| 10. | A stick in water appears broken due to ? | |
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total internal reflection
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reflection of light
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both total internal reflection and reflection of light
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refraction of light
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