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Does density affect the refractive index of a liquid?


hypark

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So I am doing a research paper but im not sure if density affects the bending of light. I have once read a short experiment on the net explaining that density does not affect how much light would bend.

http://www.usc.edu/CSSF/History/2007/Projects/J1605.pdf

 

Well, im doing an experiment on the refraction of light and it seems that density doesnt affect the refractive index of the substance.

This is the information i got from the web. (i computed for the change in the speed of light by using 1/(refractive index) = change in the speed of light.

68.03% means the speed is 68.03% of the normal speed of light.

--------------refractive index-------change in speed--------density

oil----------------=1.47------------0.680272 (68.03%)----0.92 g/mL

water-------------=1.32356--------0.755538 (75.55%)----1 g/mL

alcohol(Isopropyl)--=1.3772---------0.726110 (72.61%)----0.785g/mL

As you can see in my little research, density really doesnt affect refractive index.

Now in my real experiment, I found out that oil refracts the most light, next to alcohol then water. if you base it on the research it fits. The more refractive index, the mor elight bends, but density didnt affect the refraction).

But my experiment might have been wrong, so i am not 100% sure of this refractive index being changed by density.

 

Hope there are experts on this subject who can replay back soon:-)

thank you,

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Density does indeed affect the refractive index.

 

My knowledge is mostly about gasses (as they are actually compressible).

 

You take say nitrogen and place it in a refractometer, you then increase the pressure of the nitrogen and you can see a fringe shift, this is direct evidence that the density has changed the refractive index.

 

This doesn't always hold between materials.

 

Your best bet is just trawling the web looking for materials and their densities.

 

luxpop might be a good place to find index of refractions, but I don't know how many liquids they have.

 

You might also want to investigate matching fluids and their relative densities...

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i just did a post about the refractive indexes of oil, alcohol and water:

oil----------------=1.47------------0.680272 (68.03%)----0.92 g/mL

water-------------=1.32356--------0.755538 (75.55%)----1 g/mL

alcohol(Isopropyl)--=1.3772---------0.726110 (72.61%)----0.785g/mL

got them from the web so it should be pretty accurate, i check many web sites and they had the some info.

Let me explain my table: (R.I. = refractive index)

-oil has the highest refractive index from the three but the second highest density.

-water has the least refractive index but has the greatest density.

-alcohol has a refractive index close to water(only0.05 difference) but still alcohol refracts more light(more R.I). it has the least density.

 

-The more slowed down the speed of light, the more light bends away from its original path.

-should I base the substances' ability to refract light with the RI or the density? im sure the RI but does density have any connection with a liquid's RI?

 

*So if you are gonna arrange the 3 liquids by their ability to refract light from the most to the least how would it be and why?

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Use the refractive index.

 

There is a direct relationship between the amount the light bends and the refractive index (Snell's Law).

 

If you change the density of a particular material it will change that materials refractive index, but there are other more significant factors.

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As you can see in my little research, density really doesnt affect refractive index.

Now in my real experiment, I found out that oil refracts the most light, next to alcohol then water. if you base it on the research it fits. The more refractive index, the mor elight bends, but density didnt affect the refraction).

But my experiment might have been wrong, so i am not 100% sure of this refractive index being changed by density.

 

The problem is that you are changing two variables at the same time, which means you can't discern what effects are present. A change index could be caused by both material and density.

 

As Klaynos has explained, you can take a gas and change its density, and see that index does actually depend on density. So any contrary data you've obtained indicates that the change in material has an even larger effect.

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