Ray Optics and Optical Instruments

Related Questions

• If an object is placed $10cm$ infront of a concave mirror of focal length $20cm,$ the image will be

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• The exposure time of a camera lens at the $\frac{f}{2.8}$ setting is $\frac{1}{200}$ second. The correct time of exposure at $\frac{f}{5.6}$ is

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• If ${{\mu }_{_{0}}}$ be the relative permeability and ${{K}_{0}}$ the dielectric constant of a medium, its refractive index is given by

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• If ${{\varepsilon }_{0}}$ and ${{\mu }_{0}}$ are respectively, the electric permittivity and the magnetic permeability of free space, $\varepsilon $ and $\mu $ the corresponding quantities in a medium, the refractive index of the medium is

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• In an astronomical telescope, the focal lengths of two lenses are 180 cm and 6 cm respectively. In normal adjustment, the magnifying power will be

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