CRITICAL ANGLE
REFRACTION VIA SNELL'S LAW FOR WAVES GOING INTO A HIGHER VELOCITY MATERIAL CAN CAUSE
TOTAL INTERNAL REFLECTION
WHERE TRANSMITTED WAVE IS ALONG INTERFACE
IN THE EARTH, THIS CAUSES
REFRACTED WAVES ALONG THE BASE OF THE CRUST / TOP OF MANTLE (MOHOROVICIC DISCONTINUITY)OTHER APPLICATIONS INCLUDE FIBER OPTICS WHERE LIGHT IS "TRAPPED" IN A LOW VELOCITY FIBER
