Question

Find the focal length of the lens having power -1.2D

Answer 1

Power = 1 / focal length

-1.2 = 1 / f

So. f = -0.833 m

Answer 2

Hey mate here is your answer

Power of lens = -1. 2 D
Power of a lens ' p ' = 1/f
Focal length = 1/-1.2
= -0. 833

Hope it helps you
Thank you