An object is kept in front of a lens of focal length + 10 cm. Describe the nature of the image in the following cases . : (1) The object distance is 25 cm. (2) The object distance is 5 cm.

Explanation

Since the focal length of the lens ( + 10 cm) is positive , it is a convex lens.
(1) If an object is kept at 25 cm from the lens, the image will be real , inverted an smaller than the object.
(2) If an object is kept at 5 cm from the lens, the image will be virtural , erect and larger than the object.