A person cannot see distinctly any object placed beyond 40cm from his eye. Find the power of lens whicTFwill enable him to see distant stars clearly is?.

Explanation

To solve the problem of finding the power of the lens that will enable a person to see distant stars clearly, we will follow these steps:

### Step 1: Understand the Problem
The person can see objects clearly only up to 40 cm (the near point). Beyond this distance, he cannot see clearly. We need to find a lens that will allow him to see objects at infinity clearly.

### Step 2: Define the Variables
- The maximum distance at which the person can see clearly (near point) is \( d = 40 \, \text{cm} = 0.4 \, \text{m} \).
- The object distance for distant stars can be considered as \( u = -\infty \) (the negative sign indicates that the object is on the opposite side of the lens).
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