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Define Its Magnifying Power and Write the Expression for It?

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Question

Define its magnifying power and write the expression for it?

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Solution

Magnifying Power: The magnifying power is the ratio of the angle α subtended at the eye by the final image to the angle β which the object subtends at the lens or the eye.

`m≈ β/α h/f_e  . f_o/h = f_o/f_e`

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2012-2013 (March) All India Set 3

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Useful Constants & Relations:

1 Charge of a proton e 1.6 × 10-19 C
2 Speed of light in vacuum c 3 × 108 ms-1
    1 u = 931 MeV

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