The image behind a convex mirror radius of curvature 970 cm

The image behind a convex mirror (radius of curvature = 97.0 cm) is located 39.0 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?

Solution

R = 97.0 cm, f = -R / 2 = -48.5 cm

d_i = - 39 cm

1/d_o + 1/d_i = 1/f

1/d_o = 1/-48.5 - [1/-39]

d_o = 199 cm

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m = -di / do = 39 / 199

m = 0.196