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Karnataka Board PUCPUC Science Class 11

The Distance of the Eye-lens from the Retina is X. for a Normal Eye, the Maximum Focal Length of the Eye-lens - Physics

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Question

The distance of the eye-lens from the retina is x. For a normal eye, the maximum focal length of the eye-lens

Options

  •  = x

  • < x

  • > x

  •  = 2 x

MCQ

Solution

 = x

For a normal eye, we have:
Far point at which the object can be placed, u=∞

Distance between the eye lens and the retina, v=x

Thus, we have:

`1/f = 1/v-1/u`

`=> 1/f =1/x -1/∞`

⇒ f=x

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Optical Instruments: the Eye
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Chapter 19: Optical Instruments - MCQ [Page 431]

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HC Verma Concepts of Physics Vol. 1 [English] Class 11 and 12
Chapter 19 Optical Instruments
MCQ | Q 7 | Page 431

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