Question

The image behind a convex mirror (radius of curvature = 56.0 cm) is located 18.0 cm from the mirror. (a)Where is the object located (give the distance to the mirror) and (b) what is the magnification of the mirror?

Answer 1

(a) For convex mirror both focal length (f) and image distance (v) are negative.

So here focal length, f= - R/2 =- 56/2 = -28 cm, where R is the radius of curvature.

And image distance v= -18 cm. If u be the object distance from mirror then we have

Replacing v and f with proper sign we get  u= + 50.4 cm.

(b) We know that Magnification is equal to the ratio of image distance to the object distance. So if we consider only magnitude then magnification (M) is given by

So we get M = 0.36.