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A person cannot clearly see distance mor...

A person cannot clearly see distance more than 40 cm. He is advised to use lens of power.

A

`-2.5 D`

B

`2.5 D`

C

`-6.25 D`

D

`1.5 D`

Text Solution

Verified by Experts

The correct Answer is:
B, D
For the remedical lens, `u = oo`,
v = - 40 cm = - 0.40 m
`therefore " " (1)/(f) = (1)/(v) - (1)/(u) = (1)/(-0.40) - (1)/(oo) = - 2.5 rArr P = - 2.5 D`
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