A lamp emitting red light is placed at the bottom of a tank of liquid with depth H = 16.0 cm and index of refraction n = 1.38 (for red light). Above the liquid is air, which has an index of refraction of 1.00. On the surface of the liquid above the light, an observer sees a bright circle with radius R.
(a) Why does the observer see a bright circle on the surface?
o because the pupils in the observer's eyes are circular
o because light striking the surface outside of the circleexperiences total internal reflection
o because the lamp is circular
(b) Calculate the radius of the bright circle seen by the observer.
Please explain how to calculate the radius of the circle as seen by the observer.
