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(Ii) the Power of a Lens is +2.0 D. Find Its Focal Length and State What Kind of Lens It Is. - Physics

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Question

The power of a lens is +2.0 D. Find its focal length and state what kind of lens it is.
Numerical
One Line Answer
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Solution

Focal length (in metres) = `1/"power(in dioptres)"`

Focal length (in metres) = `1/2` = 0.5m = 50 cm

Since, the focal length is positive, the lens is aconvex lens.

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Chapter 2: Light - Exercise 2.2 iii [Page 103]

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Frank Physics - Part 2 [English] Class 10 ICSE
Chapter 2 Light
Exercise 2.2 iii | Q 2.2 | Page 103

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