Ray Optics and Optical Instruments

Related Questions

• The radius of the convex surface of plano-convex lens is 20 cm and the refractive index of the material of the lens is 1.5. The focal length of the lens is

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• The focal length of objective and eye-piece of a telescope are 100 cm and 5 cm respectively. Final image is formed at least distance of distinct vision. The magnification of telescope is

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• Finger prints on a piece of paper may be detected by sprinkling fluorescent powder on the paper and then looking it into

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• An object is placed at $20cm$ from a convex mirror of focal length $10\,cm.$ The image formed by the mirror is

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• The length of a telescope is 36 cm. The focal lengths of its lenses can be

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