A half diminished virtual, erect image is formed 12 cm closer to the lens than the object when the object is placed in front of a spherical lens. What type of lens is used and what is its focal length?

A half diminished virtual, erect image is formed 12 cm closer to mirror than the object, when the object is placed in front of a spherical mirror. What type of mirror is used and what is its focal length?

A virtual, erect, thrice magnfiied image is formed on the same side of the lens as the object. The image is formed 12 cm behind the object. What type of lens is used and hwat is its focal length? Draw the scheme diagram.

The power of a lens is -5D. What is the nature of the lens and what is the focal length?

The focal length of a spherical lens is 50 cm. The power of the lens in Dioptre is

When a object placed between F and 2F in front of a convex lens, the image formed is ___