A concave lens forms the image of an object which is:

1. virtual, inverted, and diminished
2. virtual, upright, and diminished
3. virtual, inverted, and enlarged
4. virtual, upright, and enlarged.

For a convex lens when the object is at 2F₁, then image is formed at :

1. F₂
2. 2F₂
3. beyond 2F₂
4. infinity

For a concave lens, when the object is at a distance equal to the focal length of the lens, the image is formed at :

1. optical centre
2. second focus
3. first focus
4. mid point between the optical centre and second focus of the lens

A blue light beam forms an image of an object using a convex lens. If the blue light is replaced by red light, how will the image change?

1. Image will shift closer to the lens and become smaller.
2. Image will shift farther from the lens and become larger.
3. The position of the image will not change, only its brightness changes.
4. No change will be seen