A convex lens, of focal length 25 cm, and a concave mirror, of radius of curvature 20 cm. are placed co-axially 40 cm aprat from each other. An incident beam, parallel to the principal axis, is incident on the convex lens. Find the position and nature of the image formed by this combination.

Explanation

To solve the problem step by step, we will analyze the situation involving the convex lens and the concave mirror.

### Step 1: Identify the parameters
- Focal length of the convex lens, \( f_L = +25 \, \text{cm} \)
- Radius of curvature of the concave mirror, \( R = -20 \, \text{cm} \) (negative because it is a concave mirror)
- Focal length of the concave mirror, \( f_M = \frac{R}{2} = \frac{-20}{2} = -10 \, \text{cm} \)
- Distance between the lens and mirror, \( d = 40 \, \text{cm} \)

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