Define power of a lens and write its unit – InterviewSolution

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1.	Define power of a lens and write its unit
Answer» Power of a lens : Power of a lens is defined as its bending ability and is measured as reciprocal of focal length in metre. `therefore" Power of a lens (P)"=(1)/("f (in metres)")=(100)/("f(in cms)")` `"Unit" rarr "Dioptre (D)"`

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