A narrow light beam traveling through air strikes a calm
PHYSICS · Multi-part · CBSE · Physics · Light — Reflection and Refraction · Light — Reflection and Refraction
Problem
A narrow light beam traveling through air strikes a calm, horizontal water surface at an angle of 20∘ measured from the water’s surface (that is, 20∘ above the plane of the surface).
(a) Determine the angle of incidence measured relative to the surface normal.
(b) Determine the angle of reflection measured relative to the surface normal.
(c) Determine the angle that the reflected beam makes with the water’s surface.
(d) Suppose the same beam instead strikes the surface at 20∘ measured from the normal. Without calculation, state and explain how the answers to parts (b) and (c) would differ from those obtained above.