Question

Which of the lenses with focal length 10 cm, 20 cm, 25 cm, and 50 cm has maximum power?
(A) 50 cm
(B) 25 cm
(C) 20 cm
(D) 10 cm

Answer 1

P = 1/focal length

maximum power = minimum focal length

focal length of 10cm has max power

Answer 2

" D "

We know that,

power = 1 / focal length

This means that if focal length is decreased then the power of lens will be more.

Here also out of all options least focal length was of option " D " .Hence, option " D " is correct.