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 beam of light is converging towards a point $I$ on a screen. A plane glass plate whose thickness in the direction of the beam = $t$, refractive index = $\mu $, is introduced in the path of the beam. The convergence point is shifted by

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• Which of the following statement is true

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• An object is placed first at infinity and then at 20 cm from the object side focal plane of the convex lens. The two images thus formed are 5 cm apart. The focal length of the lens is

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• A glass convex lens $({{\mu }_{g}}=1.5)$ has a focal length of $8\,cm$ when placed in air. What would be the focal length of the lens when it is immersed in water ( ${{\mu }_{w}}=1.33$)

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