Question

(I) The real image of an object placed between \(f\) and \(2f\) from a convex lens can be seen on a screen placed at the image location. If the screen is removed, is the image still there? Explain.
(II) Plane and convex mirrors produce virtual images of objects. Can they produce real images under some circumstances? Explain.

Hint:

A real image is formed by actual intersection of light rays and therefore exists even without a screen. A plane mirror or convex mirror can form a real image when the object for the mirror is itself virtual.

Answer 1

(I) Real Image and Removal of Screen

Step 1: Understand the formation of a real image. A real image is formed due to the actual convergence of light rays. The rays physically meet at the image point. Therefore the image exists independently of the screen.

Step 2: Role of the screen. The screen merely intercepts the converging rays and makes the image visible. It does not create the image.

Step 3: Conclusion. Even after removing the screen, the rays continue to converge at the same location. Hence the real image still exists. However, it cannot be directly seen unless a screen or an eye is placed at the image position. \[ \boxed{ \text{Yes, the image still exists even after the screen is removed.} } \] (ii) (II) Can Plane and Convex Mirrors Produce Real Images?

Step 1: Normal behaviour of mirrors. A plane mirror normally produces a virtual image behind the mirror. Similarly, a convex mirror generally forms a virtual, erect and diminished image.

Step 2: Consider a virtual object. If the incident rays reaching the mirror are already converging, the mirror may receive a virtual object. Under such circumstances the reflected rays can actually meet in front of the mirror.

Step 3: Formation of real image. For a suitably placed virtual object,
• a plane mirror can produce a real image,
• a convex mirror can also produce a real image. Thus the nature of the image depends on the nature and position of the object presented to the mirror. \[ \boxed{ \text{Yes, both plane and convex mirrors can produce real images if the object is virtual.} } \]