23-1 Ray Model of Light
• Light travels in a straight line so a ray model is used to show what is happening to the light
• This model assumes light to travel in a straight line and is represented by narrow lines called light rays
23-3 Formation of Images by Spherical Mirrors
• Convex – reflects from the outside of the sphere, rearview mirrors
• Concave – reflects from the inside of the sphere, cosmetic mirrors
Mirror Equation
• Where• do is the object distance• di is the image distance• f is the focal length
io ddf
111
Magnification Equation
• Where• m is the magnification • ho is the object height• hi is the image height• do is the object distance• di is the image distance
o
i
o
i
d
d
h
hm
• Sign gives the correct location and orientations of the image
• If hi + then upright, - inverted
• If di or do + then in front of mirror, - behind mirror