Consider a wave from crossing a boundary between the medium through which it is
ID: 2001891 • Letter: C
Question
Consider a wave from crossing a boundary between the medium through which it is traveling andenters water (a denser medium with higher n=1.33).
a) Which of the following would most closely approximate its new angle of travel (in the water)relative to the boundary? Do not use any mathematics and assume the wave initially approached theboundary at an angle of 30 degrees relative to the boundary. Explain your answer physically.
~15 degrees ~30 degrees ~45 degrees
b) Verify your “guess” to (a) using Snell’s Law. Include a rough sketch of the problem with your
answer.
Explanation / Answer
a)
It would be less than 30 degrees, since as it enters from a rarer medium to denser medium, the ray bends toward th normal, hence roughly 15 degrees
b)
N1 sin(theta 1) = N2 sin(theta 2)
1 sin30 = 1.33 sin theta 2
theta 2 = 22.08 degrees