Unit: Waves
Year: 1994 Question#: 46
Question: In the diagram below, a ray of monochromatic light (wavelength = 5.9 x 10-7) reaches the boundary between medium X and air and follows the path shown.
Which medium is most likely medium X?
(1 ) diamond
(2 ) flint glass
(3 ) Lucite
(4 ) water
What is this question really asking?
Explanation by: Jessica S
[ Return to question menu ]
Answer 1
Diamond
INCORRECT
This is a question testing your ability to plug values into a formula, namely Snell's law, which says that n1Sin X1 = n2Sin X2, where X is the angle from the normal in degrees, and n is the absolute index of refraction for the material, provided the wavelength of light is 5.9 x 10-7 meters, which it is in this problem. Try this problem again with this in mind. return to top
Answer 2
Flint Glass
INCORRECT
This is a question testing your ability to plug values into a formula, namely Snell's law, which says that n1Sin X1 = n2Sin X2, where X is the angle from the normal in degrees, and n is the absolute index of refraction for the material, provided the wavelength of light is 5.9 x 10-7 meters, which it is in this problem. Try this problem again with this in mind. return to top
Answer 3
Lucite
INCORRECT
This is a question testing your ability to plug values into a formula, namely Snell's law, which says that n1Sin X1 = n2Sin X2, where X is the angle from the normal in degrees, and n is the absolute index of refraction for the material, provided the wavelength of light is 5.9 x 10-7 meters, which it is in this problem. Try this problem again with this in mind. return to top
Answer 4
Water
CORRECT
This is a question testing your ability to plug values into a formula, namely Snell's law, which says that n1Sin X1 = n2Sin X2, where X is the angle from the normal in degrees, and n is the absolute index of refraction for the material, provided the wavelength of light is 5.9 x 10-7 meters, which it is in this problem. You did it correctly. In this problem n
n1 x Sin 49° = 1.00 x Sin 90°
n1 = 1.33.
Looking on the chart for Absolute indices of refraction, we get water's is equal to 1.33, therefore medium X must be water. return to top
What's this question really asking?
This question is testing your ability to use Snell's Law,
n1Sin X1 = n2Sin X2 return to top
