Question

What is meant by power of a lens? You have 3 lens L. 1 L 2 L 3 of power +10d, +20d ,-10d respt. State the nature and focal length of image of an object placed at 15cm from the lens draw the ray daig. In support of ur ans​

Answer 1

Answer: power of a lens is defined as the reciprocal of its focal length as we know that we have three lens .

1) L1 - Convex lens (Converging lens) , focal length is 10 m.

2) L2- Convex lens (Converging lens) , focal length is 20 m.

3) L3- Concave lens (Diverging lens) ,focal length is 10 m.