Where should an object be kept before a convex lens such that the image is real and twice the size. Given focal length of lens is 10 cm.

Explanation

To find the position of the object in front of a convex lens such that the image formed is real and twice the size of the object, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Values:**
- Focal length of the convex lens (F) = +10 cm
- Magnification (M) = -2 (since the image is real and twice the size of the object)

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