What is the index of refraction of this substance?

AI Thread Summary
The index of refraction of a substance can be calculated using the speed of light in water, which is approximately 2.25 x 10^8 m/s. Given that the speed of light in the substance is 79% of this value, it results in a speed of 1.78 x 10^8 m/s. The index of refraction is then determined by the ratio of the speed of light in a vacuum to the speed of light in the substance. The final calculation confirms the index of refraction for the substance. This discussion highlights the method for calculating the index of refraction based on the speed of light in different mediums.
vucollegeguy
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The speed of light in a certain substance is 79.0% of its value in water.
What is the index of refraction of this substance?


Here's what I've done so far:

(3.0*10^8 m/s)(0.79) because its 79%.
In water, the n=1.003.

I'm not sure where to go from there.
Any help would be greatly appreciated!
Thanks in advance.
 
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vucollegeguy said:
The speed of light in a certain substance is 79.0% of its value in water.
What is the index of refraction of this substance? Here's what I've done so far:

(3.0*10^8 m/s)(0.79) because its 79%.
In water, the n=1.003.
No, that's n for air.
n for water is ____?
The speed of light in water is ____?
 
correction:
n=1.33
and the speed of light in water (3x10^8)/(1.33)=2.25x10^8
 
That's right. And:
vucollegeguy said:
The speed of light in a certain substance is 79.0% of its value in water.
Hope that's enough.
 
Since 79%, mulitplying (2.26x10^8)(0.79)= 1.78x10^8.
Correct?
 
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