Ray Optics and Optical Instruments

Related Questions

• A combination of two thin lenses of the same material with focal lengths ${{f}_{1}}$ and ${{f}_{2}}$, arranged on a common axis minimizes chromatic aberration, if the distance between them is

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• A convex lens of focal length $0.5 m$ and concave lens of focal length $1 m$ are combined. The power of the resulting lens will be

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• A beam of parallel rays is brought to a focus by a plano-convex lens. A thin concave lens of the same focal length is joined to the first lens. The effect of this is

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• A triangular prism of glass is shown in the figure. A ray incident normally to one face is totally reflected, if $\theta ={{45}^{o}}$. The index of refraction of glass is

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• An object is immersed in a fluid. In order that the object becomes invisible, it should

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