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A person's near point is 50 cm and his f...

A person's near point is `50 cm` and his far point `3m`. Power of the lenses he requires for
`(i)` reading and
`(ii)` for seeing distant stars are

A

`- 2 and 0 . 33 D`

B

`2 D and - 0.33 D`

C

`- 2 D and 3 D`

D

`2 and -3D`

Text Solution

Verified by Experts

The correct Answer is:
B
For correcting the near point , required focal length
`f=(50xx25)/((50-25))=50cm`
So power `P=(100)/(50)=+2D`
For correcting the far point , required focal length
f=- (defected for point )=- cm
`thereforeP=-(1)/(3)D=-0.33D`
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