Answer to Question #157892 in Atomic and Nuclear Physics for syed

Question

A plane mirror and a concave mirror of radius of curvature 60 cm are placed facing each other with a point object at the centre of them, if the image formed by first reflection at the spherical mirror and then at the plane mirror coincides with the object then the separation between two mirrors will be

Answer 1

$$\frac{1}{f}=\frac{1}{v}+\frac{1}{u}\\\frac{1}{v}=\frac{1}{-30}-\frac{1}{-0.5x}\\v=\frac{-30x}{x-60}$$

$$x+\frac{x}{2}=\frac{30x}{x-60}\\x=80\ cm$$