A convex mirror produces an erect image half the object size when the object is 30 cm from the pole. What is the focal length magnitude?
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A convex mirror produces an erect image half the object size when the object is 30 cm from the pole. What is the focal length magnitude?

G1 Physics · Accepted Answer

m=+1/2 gives v=+15 cm for u=−30 cm. Then 1/f=1/v+1/u=1/15−1/30=1/30, so f=+30 cm.