A beam of light inside water strikes the water–air surface. The limiting angle of incidence in water for which the light just emerges into air is found to be 48∘.
(a) Calculate the refractive index of water with respect to air.
(b) Using the value obtained in (a), find the speed of light in water. Take the speed of light in vacuum as 3.0×108m s−1.
(c) A fish at a depth sends a ray towards the surface at an angle of incidence of 30∘ inside water. State, with reason, whether this ray will emerge into air or be totally internally reflected.
a. Calculate the refractive index of water with respect to air, given that the limiting angle of incidence in water is 48∘.
b. Using the value obtained in (a), find the speed of light in water. Take the speed of light in vacuum as 3.0×108m s−1.
c. A fish at a depth sends a ray towards the surface at an angle of incidence of 30∘ inside water. State, with reason, whether this ray will emerge into air or be totally internally reflected.