Question

What is meant by power of a lens? What does its sign (+ve or -ve) indicate? State its S.I. unit. How is this unit related to focal length of a lens?(Delhi - 2016)

Answer 1

Answer:

the ability to converge or diverge light is called power of a lens

Answer 2

Power of a lens

Meaning:

• The reciprocal of the focal length of the lens is called its power of lens.

Signs:

• If the power of the lens is denoted by positive (+) sign it means that it is a convex lens.
• On the other hand, the negative (-) sign indicates that the lens is concave.

S.I unit and its relation with focal length

• Its S.I unit is dioptre and it is denoted by symbol 'D'.
• As the value of 'D' denotes the power of the lens, the value of 'f' denotes the focal length.
• It is mathematically represented as 1 D = 1 $m^{-1}$.

Learn more about such concept

If the power of lens is 2D then what is its focal length​

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RELATION BETWEEN POWER OF LENS AND FOCAL LENGTH

https://brainly.in/question/6814101