Which type of lens can form real and inverted images, as well as virtual and erect image of an object ?

Answer

To determine which type of lens can form both real and inverted images as well as virtual and erect images, we can follow these steps:

### Step 1: Understand the Types of Images
- **Real Image**: This type of image is formed when light rays converge and can be projected onto a screen. It is always inverted.
- **Virtual Image**: This image is formed when light rays appear to diverge from a point, and it cannot be projected onto a screen. It is always erect.

### Step 2: Identify the Types of Lenses
- **Convex Lens**: A convex lens is thicker in the middle than at the edges and converges light rays that pass through it. It can form both real and virtual images depending on the position of the object.
- **Concave Lens**: A concave lens is thinner in the middle and diverges light rays. It only forms virtual images that are erect.

### Step 3: Analyze the Convex Lens
- When an object is placed beyond the center of curvature (more than twice the focal length), the convex lens forms a real and inverted image.
- When the object is placed between the focal point and the lens, the convex lens forms a virtual and erect image.

### Conclusion
Based on the analysis, the type of lens that can form both real and inverted images as well as virtual and erect images is the **Convex Lens**.

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