Question

The focal length of a concave mirror is f and the distance of the object to the principal focus is p. Then

the ratio of the size of the image to the size of the object is:

A) p/p

B) p/f

C) fp

D) pf​

Answer 1

Answer:

As per the sign convention for mirror, the focal length is taken as negative as it is measured opposite to the direction of light. Hence, focal length f = -f. The distance of the object from the principal focus is p. Hence, the distance of object from the mirror [ u ] = p+ f.