Index of refraction and speed of light

AI Thread Summary
To find the speed of light in carbon tetrachloride, the formula v = c/n is applied, where c is the speed of light in a vacuum and n is the index of refraction of the medium. The correct calculation involves dividing the speed of light (approximately 3 x 10^8 m/s) by the index of refraction for carbon tetrachloride (n = 1.46), resulting in a speed of about 2.05 x 10^8 m/s. The index of refraction for crown glass (n = 1.52) is not relevant for calculating the speed in the liquid, unless additional context about refraction angles is provided. The confusion arises from the presence of two indices of refraction, but only the one for the medium in question is needed for this calculation. Understanding the relationship between speed, index of refraction, and medium is crucial in optics.
Yusufzai
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Had this question in a test today, :).

Homework Statement



Carbon tetrachloride (n = 1.46) is poured into a container made of crown glass (n = 1.52). What's the speed of light in the liquad?




Homework Equations


v=c/n


The Attempt at a Solution



I just multiplied 1.46 by the speed of light. I wanted to know if this is the correct way to do it, what confused me the most was the 2 index of refraction.
 
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To get the speed, you just divide c by n = 1.46. Using the formula you gave correctly yourself. If you multiply c with a number bigger then 1, you'd get a speed greater then that in vacuum.

I can't see why you're given the n value for the crown glass material, since the speed in the liquid wouldn't depend on it. Are you sure there wasn't any questions about the refraction angle, or such, where both refractive indexes are used?
 
v= c/n
c is the speed of light
v is the speed in the new medium
 
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