The size of the real image produced by a convex lens of focal length F is ' m ' times the size of the object. The image distance from the lens is

Step-by-step solution

From lens formula, 1 v - 1 u = 1 ~F For a convex lens, u is negative, v and F are positive. aligned & 1 v - 1 - u = 1 ~F & 1 v = 1 ~F - 1 u aligned Multiplying by v , aligned 1 & = v F - v u 1 & = v F - m ( v u = m ) v F & =1+ m v & = F (1+ m ) aligned