A person wants a real image of his own, ( 3 ) times enlarged. Where should he stand infront of a concave mirror of radius of curvature ( 30 ~cm ) ?

Step-by-step solution

Given, magnification ( =3 ); radius of curvature ( =30 ~cm ) Using mirror formula, ( 1 f = 1 v + 1 u ) Now ( m= -v u -3= -v u v=3 u ) Also ( f= R 2 = 30 2 =15 ~cm ) Therefore, ( 1 -15 + 1 3 v + 1 u -1 15 = 4 3 u -3 u=60 ) ( u=-20 ~cm ) Thus, the e-ser