Question

calculate the power of a concave lens of focal length 2 metere​

Answer 1

Given :-

• Focal length of concave lens , f = - 2 m

(focal length of concave lens is always negative)

To find :-

• Power of concave lens

Formula used :-

• Relation b/w Power (P) of lens and focal length (f) of lens

       P = 1 / f

( while finding Power , focal length should be in metres )

Solution :-

Using the formula to calculate power

→   P = 1 / f

→  P = 1 / -2

→ P = -0.5 D

Therefore,

Power of concave lens of focal length 2 m is -0.5 Dioptre .

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• The power of a lens is defined as the reciprocal of its focal length in metres.

• Power of lens is directly proportional to deviation of light ray.

• S.I. unit of Power is Dioptre represented by D.

• Concave lens and convex lens have negative and positive powers respectively.

• Power of combined lenses is the algebraic sum of the powers of each lens.

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Answer 2

Here is u r answer Buddy

Mark as Brainliest answer please my friend

Sol :-

P = 1 / f

P = 1 / (–2)

P = –½

P = –0.5 D

Hope this will help u