Question

A Concave mirror forms a real image which is twice the size ofthe object. If the object is located 20 cm from the mirror, theradius os curvature must be about: a.) 13 cm b.) 20 cm c.) 27 cm d.) 40 cm

Answer 1

use of m= -v/u and take u=-20 and then find v v = 40 option (d)