Question

If the radius of curvature is negative then the focal length is negative or positive

Answer 1

❥ A᭄nswer✭࿐

By convention, distances are measured, along the central axis, as positive from the mirror in the direction of the object and negative away from the object. Hence the radius of curvature and the focal length are positive for concave mirrors and negative for convex mirrors.

Figure 1 :- The three types of mirrors.