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A person wants to read a book placed at ...

A person wants to read a book placed at `20 cm`, whereas near point of his eye is `30 cm`. Calculate the power of the lens required.

Text Solution

Verified by Experts

The correct Answer is:
`1.67 D`
Here, `d = 20 cm, x' = 30 cm, P = ?`
As `f = (x' d)/(x' - d) = (30 xx 20)/(30 - 20) = 60 cm, P = (100)/(f) = (100)/(60) = 1.67 D`.
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