Two thin lenses, both of 10 cm focal length- one convex and other concave, are placed 5 cm apart. An object is placed 20 cm in front of the convex lens. Find the nature and position of the final image.

Explanation

To solve the problem of finding the nature and position of the final image formed by the two lenses, we will follow these steps:

### Step 1: Identify the lenses and their properties
- We have a convex lens with a focal length \( f_1 = +10 \, \text{cm} \) and a concave lens with a focal length \( f_2 = -10 \, \text{cm} \).
- The distance between the two lenses is \( d = 5 \, \text{cm} \).
- An object is placed \( u_1 = -20 \, \text{cm} \) (the negative sign indicates that the object is on the same side as the incoming light) in front of the convex lens.

### Step 2: Calculate the image formed by the convex lens
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