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FrozenGate by Avery

Science experiment

T

tiansili

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Jan 10, 2013
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Hello,
Now, I have decided to create an experiment based on laser beams, and how they react, so this is the question... "Can you change the speed of light?"
I know that the speed of light can be changed depending on the medium its passing through, however can anybody explain this video to me?
Bending a laser beam. Experiment. - YouTube
I don't quite understand the refraction...:thinking:
Anyone care to explain the mystery behind it? Also, I would really appreciate sources
I am planning to conduct a similar experiment, since my own ideas require actual instruments for measurement..
Any new ideas will be welcome, since there may be something more appropriate,
Thanks for helping me!:thanks:
 





First of all, Welcome to the forum since you're a new member.. This is quite fascinating stuff :beer:
I hope someone would get you your answers but posting three (3) identical threads will get you negative rep from the members and the ban hammer might not be so forgiving!
 
sinner said:
I hope someone would get you your answers but posting three (3) identical threads will get you negative rep from the members and the ban hammer might not be so forgiving!
Click to expand...

Exactly sinner.

tiansili---You need to delete your multiple posts if you expect any positive response--use edit function to delete the other 2 identical posts.

Other than that Welcome---interesting project.

Here are 2 articles about creating and what slow light concept is.

Physicists Slow Speed of Light

Slow light - Wikipedia, the free encyclopedia
 
Great video !
Bending works like this .. light travels slower in denser medium. To bend a beam gradually you first you speed gradient - gradual change of medium density. Here it's done with sugar. There will be more sugar near the bottom, and less near the top.
Now image beam as a cart with single wheel on each side, both fixed on single axis. Rotated so the lower wheel is in deeper, denser water, and the upper wheel is in lighter water. The lower wheel will move slower than the upper wheel .. thus the cart will turn down. And it works exactly the same with light, or sound.
I did some simulation of underwater sound propagation, where this effect is very strong. The wave of light (yeah, I know light is not exactly a wave, thank you), or sound will travel slower at on depth, and faster in another depth .. so the wave-front and direction of propagation will turn.
Just an interesting detail .. light travels slower in denser environment, but sound travels faster in denser environment.

PS. now where do I get a glass container like that ?
 
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I've merged the treads.

Try not to post duplicate threads please.
 
I think the maker of the video did a good job describing it....

The mix is not homogeneous. The sugar solution is heavier than the fresh water, and the mix creates a gradient with different concentrations of sugar in water: fresh water at the top and a heavier sugar solution at the bottom. The refractive index of water is 1.33 and 1.49 of a 80% solution of sugar.

A beam of light propagating from one medium to another with different refractive indexes changes its direction. If the change in the gradient index is very gradual the result is a curved beam.
 
bobhaha said:
I think the maker of the video did a good job describing it....

The mix is not homogeneous. The sugar solution is heavier than the fresh water, and the mix creates a gradient with different concentrations of sugar in water: fresh water at the top and a heavier sugar solution at the bottom. The refractive index of water is 1.33 and 1.49 of a 80% solution of sugar.

A beam of light propagating from one medium to another with different refractive indexes changes its direction. If the change in the gradient index is very gradual the result is a curved beam.
Click to expand...

Can you simplify your explanation just a tiny bit? If it is refracting, why is it gradual and how?
My question for my experiment right now is
How to most effectively bend light using chemicals?
I'm planning to check which chemical can increase the effect... I'm gonna do the experiment except mark the point where the laser sits and check the angle...Will it work?
Any opinions as to what to use? what mixtures?
Thank you nevertheless
 
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Refraction is result of different speed of propagation. Which depends on density. I really don't see how to explain the mechanism better then I already did.
As for the chemicals .. you need something transparent, very heavy, and it has to mix with water easily. You will have problem finding things better then sugar, I'm afraid. Sugar is also cheap and safe to handle.
 
DrSid said:
Sugar is also cheap and safe to handle.
Click to expand...

<insert lame diabeetus joke here>

DrSid said:
As for the chemicals .. you need something transparent
Click to expand...

Not necessarily. There are quite a few compounds that become clear when dissolved in water. There are others that are clear, but change color when in solution.
 
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