The critical angle in air for a particular type of glass is 39.0°. What is the speed of light in this class glass? (c = 3.00 × 108 m/s) The critical angle in air for a particular type of glass is 39.0°. What is the speed of light in this class glass? (c = 3.00 × 108 m/s) 1.91 × 108 m/s 1.89 × 108 m/s 2.00 × 108 m/s 1.94 × 108 m/s 1.97 × 108 m/s

Amichelson interferometer operating at a 600 nm wavelength has a 3.02-cm-long glass cell in one arm. to begin, the air is pumped out of the cell and mirror m2 is adjusted to produce a bright spot at the center of the interference pattern. then a valve is opened and air is slowly admitted into the cell. the index of refraction of air at 1.00 atm pressure is 1.00028.how many bright-dark-bright fringe shifts are observed as the cell fills with air?