Question

A ray of makes a transition from water (n=1.33) to air (n=1.00) with an incident angle of 85.0 degrees with respect to the surface.Find the angle of refraction with respect to the normal as is conventional.

Answer 1

The angle with respect to the normal is the complement of the given,

Ai = 90 - 85.0 deg = 5.00 degrees

Thus, note that from Snell's law,          
          
n1sin(t1) = n2sin(t2)          
          
where          
          
n1 = index of refraction of first medium =    1.33  
t1 = angle of incidence =    5   degrees  
n2 = index of refraction of second medium =    1  
t2 = angle of refraction
          
Thus,          
          
t2 =    6.66   degrees   [ANSWER]