What is the sign of the power of (i) a convex lens (ii) a concave lens ?

Explanation

To determine the sign of the power of a convex lens and a concave lens, we need to understand the relationship between the focal length of the lens and its power. The power of a lens (P) is given by the formula:

\[ P = \frac{1}{f} \]

where \( f \) is the focal length of the lens.

### Step-by-Step Solution:

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