Linear magnification of the image produced by a spherical mirror is 2.5 means that the height of the image is 2.5 times that of the object, since linear magnification (m) =Height of the image/Height of the object The mirror referred to here is a concave mirror since it produces a magnified image when an object is held either between C and F or between P and F of the mirror. A convex mirror, on theother hand, always forms a diminished image of an object.