Is it possible for the index of refraction to be zero in Snell's law?

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SUMMARY

This discussion centers on the application of Snell's Law in scenarios where light rays travel along the normal line. It establishes that while Snell's Law suggests an index of refraction (n) of zero when the angle of incidence (θi) is zero, this is incorrect because the formula for index of refraction (n=c/v) indicates that both the speed of light in a medium (v) and the speed of light in a vacuum (c) are positive. Therefore, light rays along the normal do not bend, and the angles with the normal remain zero, making the use of Snell's Law in this context problematic due to potential division by zero.

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Jimmy Chung
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Does Snell's law apply in refraction when the light ray is along the normal line? Utilizing snell's law, the index of refraction (n) would be zero.

nr= ni(sin θi)/sinθr

Sin(θi)= 0 therefore, nr=0

However,utilizing the formula for index of refraction (n=c/v), the index of refraction would not be zero as both v and c are positive.

Are light rays along the normal line and not bending refraction at all? If so, which calculation of the index of reflection is correct? Why is the other one wrong?
 
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If a light ray goes from one medium to a different medium along the normal the speed of light changes according to the ratio of the two media.

Also in this case of normal incidence there is no bending of the light ray and so the angles made by the light ray with the normal are both zero.

In investigating whether Snell's Law applies one has to be careful about any division by zero.
 
If you wanted to find the refractive index using Snells Law then I can't see why you would want to use zero angles for your experiment. It would be as pointless as wanting to calculate the speed of an object by finding the time for it to move by a zero distance.
0/0 is not determinate.
 

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