Question

A prism made of flint glass has a cross section that is an equilateral triangle. The index of refraction for red and violet light respectively in flint glass is 1.662 and 1.698. If as shown in the figure, the angle of incidence in air for both colors of light is 75.1

Answer 1

For red:

Note that from Snell's law,      
      
n1sin(t1) = n2sin(t2)      
      
where      
      
n1 = index of refraction of first medium =    1  
t1 = angle of incidence =    75.1   degrees
n2 = index of refraction of second medium =    1.662  
t2 = angle of refraction
      
Thus,      
      
t2 =    35.55285451   degrees

For the second interface,

Note that from Snell's law,      
      
n1sin(t1) = n2sin(t2)      
      
where      
      
n1 = index of refraction of first medium =    1.662  
t1 = angle of incidence =    24.447   degrees
n2 = index of refraction of second medium =    1  
t2 = angle of refraction =       
      
Thus,      
      
t2 =    43.458   degrees [final angle, red]

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For violet:

Note that from Snell's law,      
      
n1sin(t1) = n2sin(t2)      
      
where      
      
n1 = index of refraction of first medium =    1  
t1 = angle of incidence =    75.1   degrees
n2 = index of refraction of second medium =    1.698  
t2 = angle of refraction =       
      
Thus,      
      
t2 =    34.68930693   degrees

For the second interface,

Note that from Snell's law,      
      
n1sin(t1) = n2sin(t2)      
      
where      
      
n1 = index of refraction of first medium =    1.698  
t1 = angle of incidence =    25.3107   degrees
n2 = index of refraction of second medium =    1  
t2 = angle of refraction =       
      
Thus,      
      
t2 =    46.547   degrees   [final angle, violet]

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The angles are

red: 43.458 degrees
violet: 46.547 degrees [ANSWERS]