If the power of the lenses is +0.5D, find the focal length of lenses.

Academic Physics NCERT Class 10

Given: the power of the lens is +0.5D

To find: the focal length of lens

Solution:

We know, power of a lens = $\frac{1}{f}$

Here $f$ is focal length taken in metres.

So,

0.5 = $\frac{1}{f}$

$f = 2 \ metre $

So, focal length of the lens is 2 metre.

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Updated on: 10-Oct-2022

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