Question

An illuminated object lies at a distance 1.0 m from a screen. A convex lens is used to form the image of object on a screen placed at a distance 75 cm from the lens. Find (1) the focal length of lens (2)the magnification

Answer 1

An illuminated object lies at distance 1.0 m from a screen .A convex lens is used to from the image of objects on a screen placed at a distance 75 cm from the lens.
1. The focal length of lens is