Question

How does the power of a lens change if its focal length decreases to half? What is the unit of power of lens?
2 points
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Answer 1

Explanation:

इस द फोकल लेंथ बिकम ऑफ द पावर ऑफ लेंस बिकम 2 times

Answer 2

Power of lens is doubled and unit of power of lens is Diopter.

Power of a lens is inversely proportional to the focal length. The are mathematically represented in equation form as - P = 1/f. In the formula, p stands for power of lens while f stands for focal length.

Let original focal length be f, original power be P and new focal length be f', new power be P'.

P' = 1/f'

As stated, f' = (1/2)f

Keeping the values in equation-

P' = 1/(f/2)

P' = 1*2/f

P' = 2P.

Hence, new power will be two times of original power. The unit of power of lens is Diopter which is m-¹.