<p>A block of flint glass with an index of refraction of 1.66 is immersed in oil with an index of refraction of 1.33. How does the critical angle for a refracted light ray in the glass vary from when the glass is surrounded by air?
A. It remains unchanged.
B. It increases .
C. It decreases.
D. No total internal reflection takes place when
the glass is placed in the oil.
Okay so you do Sine^-1(1.33/1.66) = 53 and Sine^-1(1.00/1.66)= 37. So basically it varies in that it is increased when it is immersed in the oil, right? Many people are saying that it decreases, but if you read closely, it's asking how that angle varies from the glass surrounded by air which is 37. So whats the answer?? </p>