A diminished image of an object is to be obtained on a screen 1.0 m away from it. This can be achieved by approximately placing

Step-by-step solution

Image can be formed on the screen if it is real. Real image of reduced size can be formed by a concave mirror or a convex lens Let u = 2 f + x , then 1 u + 1 v = 1 f ⇒ 1 2 f + x + 1 v = 1 f ⇒ 1 v = 1 f - 1 2 f + x = f + x f ( 2 f + x ) ⇒ v = f ( 2 f + x ) f + x It is given that u + v = 1.0 m 2 f + x + f ( 2 f + x ) f + x = 2 f + x 1 + f f + x < 1.0 m Or 2 f + x 2 f + x < 1.0 m Or 2 f + x 2 < ( f + x ) This will be true only when f < 0.25 m