A convex mirror of focal length f forms an image of the size of the object. The distance of the object from the mirror is

Question

Philoid · Accepted Answer

According to the question

Magnification (m) = (image is of the size of object).

Focal length = f (positive for convex mirror).

Object distance = -u.

Now By formula.

⇒

⇒ f + u = nf

⇒ u = nf – f

⇒ u = (n-1)f.

Therefore the object distance from the mirror is (n-1)f. Hence the option C is correct.