A convex lens forms a real and inverted image of a needle at a distance of `50 cm` from it. Where is the needle placed in front of the convex lens if the image is equal to size of the object ? Also, find the power of the lens.

Explanation

To solve the problem step by step, we will follow the principles of optics related to lenses.

### Step 1: Understand the Given Information
We know that:
- The image distance (V) is given as +50 cm (since it is a real image).
- The magnification (M) is equal to 1, which means the image size is equal to the object size.

### Step 2: Use the Magnification Formula
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