Ray Optics and Optical Instruments

Related Questions

• A microscope is focussed on a coin lying at the bottom of a beaker. The microscope is now raised up by $1$ cm. To what depth should the water be poured into the beaker so that coin is again in focus ? (Refractive index of water is $\frac{4}{3}$) [BHU 2003]

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• A simple telescope, consisting of an objective of focal length $60 cm$ and a single eye lens of focal length $5 cm$ is focussed on a distant object is such a way that parallel rays comes out from the eye lens. If the object subtends an angle $2^o$ at the objective, the angular width of the image

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• A candle placed 25 cm from a lens, forms an image on a screen placed 75 cm on the other end of the lens. The focal length and type of the lens should be

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• A convex mirror is used to form the image of an object. Then which of the following statements is wrong

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• If the wavelength of light in vacuum be $\lambda$, the wavelength in a medium of refractive index $n$ will be

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