How are power and focal length of a lens related ? You are provided with two lenses of focal length `20 cm` and `40 cm` respectively. Which lens will you use to obtain more convergent light ?

Explanation

To solve the question of how power and focal length of a lens are related, and to determine which lens will provide more convergent light, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Relationship Between Power and Focal Length**:
- The power (P) of a lens is defined as the reciprocal of its focal length (F) in meters. The formula is given by:
\[
P = \frac{1}{F}
...