A short object of length `L` is placed along the principal axis of a concave mirror aeay from focus. The object distance is `u`. If the mirror has a focal length `f`, what will be the length of the image ? You may take `L lt lt | v - f |`.

Explanation

To solve the problem of finding the length of the image formed by a concave mirror for a short object of length \( L \) placed along the principal axis, we can follow these steps:

### Step 1: Understanding the Setup
We have a concave mirror with a focal length \( f \). The object is placed at a distance \( u \) from the mirror, and the length of the object is \( L \). We need to find the length of the image formed by this mirror.

### Step 2: Define Object Points
Since the object has a length \( L \), we can define two points on the object:
- The first point \( U_1 \) is at a distance \( u - \frac{L}{2} \) from the mirror (the left end of the object).
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