To determine which symbol represents a concave mirror, let's understand the properties of concave mirrors.
Concave mirrors, also known as converging mirrors, have several distinct characteristics:
1. Focal Point (F): This is the point where parallel rays of light meeting the mirror converge after reflection.
2. Focal Length (f): This is the distance from the mirror's surface to the focal point. For concave mirrors, the focal length is always positive.
Given this information, let's analyze the options:
- Option A: +dj
- This notation doesn't directly relate to the focal length of a concave mirror.
- Option B: +f
- This indicates a positive focal length, which aligns perfectly with the property of concave mirrors having a positive focal length.
- Option C: -dj
- This notation also doesn't directly relate to the focal length of a concave mirror.
- Option D: -f
- This indicates a negative focal length, which is characteristic of convex mirrors, not concave mirrors.
Based on this analysis, the correct representation of a concave mirror is "B. +f". This signifies a positive focal length, which is a defining feature of concave mirrors.
