On reducing the focal length of a lens, its power: - Noon Academy

On reducing the focal length of a lens, its power:

Class 10 | ICSE | Physics | Refraction through a Lens | Selina

On reducing the focal length of a lens, its power:

(a) Decreases

(b) Increases

(c) Does not change

(d) First increases then decreases.

Solution:

The correct option is (b).

On reducing the focal length of a lens, the power of the lens increases. This follows from the expression of power of a lens, which is –

P = 1/f

i

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