Ray Optics and Optical Instruments

Related Questions

• A combination of two thin lenses with focal lengths ${{f}_{1}}$ and ${{f}_{2}}$ respectively forms an image of distant object at distance $60 cm$ when lenses are in contact. The position of this image shifts by $30 cm$ towards the combination when two lenses are separated by $10 cm$. The corresponding values of ${{f}_{1}}$ and ${{f}_{2}}$ are

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• The relation between $n_1$ and $n_2$, if behaviour of light rays is as shown in figure is

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• Angle of deviation $(\delta $) by a prism (refractive index = $\mu $ and supposing the angle of prism A to be small) can be given by

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• While using an electric bulb, the reflection for street lighting should be from

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• The hyper-metropia is a

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