Ray Diagrams for spherical mirrors
Finding the focal point Center of Curvature (C)- if the mirror actually was a sphere, this is the center of that sphere. Radius of Curvature (R)- distance from C to mirror. The radius is ALWAYS twice the focal length
Approximations F C
Rules for Ray diagramming You must draw 3 rays 1. parallel to a perpendicular of the mirror, returns through F 2. through F, returns parallel to a perpendicular of the mirror 3. through center of curvature (C), returns back through itself.
The three rays Ray 1 Ray 2 Ray 3 This image is in real space. p It is a real image. F q C It is upside down and smaller. The image forms here
Another Ray 1 Ray 2 Ray 3 q, this will be negative p F C This is a virtual image. It is upright and larger.
Convex mirror Focal point and radius of curvature are negative! Ray 1 q p This is a virtual image. It is upright and smaller.
Draw your own Draw a ray diagram for an object 3.5 m from a makeup (concave) mirror that has a focal length of 0.5 m. What will the image distance be? What will the magnification be? Will the image be virtual or real? Will the image be upright or inverted? Use a ruler (make a scale)