Question

A Convex lens has a focal length of 40cm calculate its powers

Answer 1

focal length=40cm=0.4m
power=1/f
so power=1/0.4=2.5dioptre
I HOPE IT WILL HELP YOU

Answer 2

hey mate....

here is your answer

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↪Focal length -> 40 cm

↪P = 1 / F (in m)  

↪P = 1 / 0.4 m

↪P = + 2 . 5D

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