Mirrors

1. Mirrors Characteristics & Ray Diagrams

2. Plane Mirrors Plane Mirror = a flat, smooth surface that reflects light by regular reflection. • Created by coating glass with Silver • Rays are reflected with equal angles of incidence and reflection

3. Plane Mirrors Vocabulary • Object = the source of spreading of light rays • Virtual Image = object seen in mirror • Same size • Same direction (up and down) • Reversed (left to right) • Appears to be behind mirror as far back as it is in front of mirror

4. Ray Diagram Properties • Mirror Line (MN) = where mirror is located • Line of Sight = line from image to an extreme angle (> 300) • Reflected Ray = line traveling down line of sight from beyond mirror (arrow pointing away from mirror) • Incident Ray = line traveling from object to where reflected ray hits mirror line (arrow pointing toward mirror)

5. Ray Diagram Properties (cont.) • Normal line = line perpendicular to mirror, starting at point where incident & reflected ray converge • Angle of Incidence = made from incident ray and normal line • Angle of Reflection = made from reflected ray and normal line • Angle of Incidence & Angle of Reflection should be equal.

6. P1 M N Reflected Ray Reflected Ray Reflected Angle P Incident Ray Incident Angle Normal Line

7. Curved Mirrors • Reflection comes from inner “caved in” surface • Rays will reflect with equal angles of incidence and reflection • Rays parallel to the principal axis reflect and cross the principal axis at a point called the “focal point”

8. Curved Mirrors (cont.) • Focal point (F) is located ½ the distance between the Center of curvature (C) and the mirror • Concave mirrors produce a “real image” because the rays converge at a location in front of the mirror

9. M Parts of a Concave Mirror f V P P1 C F R Converge light to (F) N

10. M Parts of a Convex Mirror C F Diverge light from (F) N

11. M Rays Used to Find an Image #1 #2 P P1 C F #2 image #3 #1 Image = smaller, upside down, real N