Write two characteristics of image formed when an object is placed between the optical centre and focus of a thin convex lens. Draw the graph showing variation of image distance v with object distance u in this case.

Explanation

To solve the question, we will follow these steps:

### Step 1: Identify the characteristics of the image formed by a thin convex lens when the object is placed between the optical center (O) and the focus (F).

1. **Virtual Image**: The image formed is virtual because the rays of light diverge after passing through the lens, and the image cannot be projected on a screen.
2. **Erect Image**: The image is erect, meaning it is oriented in the same direction as the object.
3. **Enlarged Image**: The image is larger than the object, hence it is highly enlarged.

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