question_answer

n silvering the convex side of a piano convex lens, focal length of the resulting mirror is: [where R = radius of convex lens, \[\mu \]= refractive index of glass]

A) \[\frac{R}{2\mu }\]        

B) \[\frac{2R}{\mu }\]

C) \[\frac{R}{\mu }\]

D) \[\frac{3R}{2\mu }\]