 a  b tan  ~  etc. so  = h / s,  = h / s’,  = h / R Snell’s Law: n a sin  a = n b sin  b n a  a = n b  b  b = (  ) n a / n b n a  + n b  n b  n a  n a /s + n b /s’ = ( n b - n a ) / R Fig (Continued) Refraction at a spherical surface – position of image. © 2003 J. F. Becker San Jose State University Physics 52 Heat and Optics

Fig Refraction at a spherical surface – height of image. © 2003 J. F. Becker San Jose State University Physics 52 Heat and Optics

Fig A glass rod in air forms a real image inside the rod. © 2003 J. F. Becker San Jose State University Physics 52 Heat and Optics

Fig First and second focal points of a converging thin lens. The numerical value of f is positive. © 2003 J. F. Becker San Jose State University Physics 52 Heat and Optics

Fig Construction used to find the image position for a thin lens. © 2003 J. F. Becker San Jose State University Physics 52 Heat and Optics

Fig First and second focal points of a diverging thin lens. The numerical value of f is negative. © 2003 J. F. Becker San Jose State University Physics 52 Heat and Optics