Question

The focal length of a lens whose power is + 2 D is


50 cm

50 m

2 m

2 cm

​

Answer 1

Answer:

f = 50 cm

Explanation:

the correct answer is 50 cm

Answer 2

Answer:

answer is 50 cm

Explanation:

Given power of lens is +2D

we know that,

Power of lens = 1/f where 'f' is the focal length of the lens

So, according to the question,

1/f=2

f = 1/2 = 0.5 m

= 50 cm as 'D' is nothing but 'm^-1'