1. Learning Outcome
Draw a ray diagram to find the position, nature and size of the image produced by a concave and convex mirrors

2. Plane Mirrors Eye sees image back here
Image is virtual and laterally inverted
Light from object reflects into eye

3. Curved (Concave) MirrorsF P c pa f
P = pole , pa = principal axis
C = centre of curvature, c = radius of curvature
F = Focal point or focus, f = focal length
f = c / 2

4. Ray Diagrams
Rule 1: An incident ray parallel to the pa is reflected back through the focal point. F

5. Ray Diagrams
Rule 2: An incident ray that passes through the focal point on the way to the mirror is reflected back parallel to the pa. F

6. Ray Diagrams
Rule 3: An incident ray headed towards the pole reflects back at an equal angle P F

7. All three combined allow you to find the image
In this example the image is inverted, diminished and real
object F P
image

8. Concave Mirrors
Concave (or converging) mirrors focus light at the focal point. F

9. Convex Mirrors Convex mirrors have a focal point behind the mirror.
Convex (or diverging) mirrors spread the light rays apart so that they appear to have come from the focal point F

10. Ray Diagrams The same rules can be applied to convex mirrors…
All convex mirror images are virtual.
object F
image