Question

If the power of a lens is – 2 D, what is its focal length?
(a) +50 cm
(b) -100 cm
(c) -50 cm
(d) +100 cm

Answer 1

• hey user !!

Answer:

C) +50 cm

Explanation:

Power of a lens is -2D, negative sign indicates it is a Concave lens. Focal length (in meters)=1/power of the lens, thus focal length=1/2=0.5m=50cm

Answer 2

Answer:

correct answer is a +50