Question

Which of the following represents a concave mirror? +f,-f,-di,+di

Answer 1

+f

Step-by-step explanation:

because you have to be really dumb to get an -f

Answer 2

fully describes the concave mirror is + f

Step-by-step explanation:

A concave mirror is a mirror where light rays are reflected reaching a point where the image is formed, therefore this mirror has a positive focal length, the amount that fully describes the concave mirror is + f

This allows defining a sign convention, for concave mirror + f, the distance to the object is + d0 and the distance to the image is + di