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The focal length of a convex lens is 20 ...

The focal length of a convex lens is 20 cm.What is the power?

Text Solution

Verified by Experts

The correct Answer is:
The power of the convex lens is SD.

Given: Focal length (f)=20 cm =0.2 m
To find: Power of the lens (P)
Formula: `P=(1)/(f(m))`
Calculation: From formula,
`P=(1)/(0.2)`
`=5D`
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