Ray Optics and Optical Instruments

Related Questions

• In an astronomical telescope, the focal length of objective lens and eye-piece are 150 cm and 6 cm respectively. In case when final image is formed at least distance of distinct vision. the magnifying power is

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• A satisfactory photographic print is obtained when the exposure time is 10 sec at a distance of 2 m from a 60 cd lamp. The time of exposure required for the same quality print at a distance of 4 m from a 120 cd lamp is

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• A concave mirror gives an image three times as large as the object placed at a distance of $20cm$ from it. For the image to be real, the focal length should be

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• A ray of light is incident on a transparent glass slab of refractive index 1.62. The reflected and the refracted rays are mutually perpendicular. The angle of incidence is

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