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Lasar Science Fair Idea HELP!

DIY

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My idea is to test how much heat is lost from a lasar if pointed through liquid and which liquid takes away the most heat. So i am wondering if there is sometthing I could use to measure the heat of the beam? If anyone else has any lasar science fair ideas, I would really like to hear them as well. Thanks:bowdown:
 





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does liquid take heat away or does it just make and beam weaking hense less heat?
 

IsaacT

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Well if you had a really stable unit, you could get an LPM and aim the beam through liquid. Take the power once behind the liquid, and once again without the liquid there. I think it would be best to measure it at the same distance, to cancel out any confounding factors like distance. As I said though, you would need a stable unit, more than likely a lab style laser. You would also need an LPM, and I am not sure how much you have available to spend on this science fair project. With that said, best of luck! And if you get some results let us know!
 

Benm

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Or you can set it up like a spectrometer: Split the beam before it enters the sample, and route it around the sample cuvette. You can then alternate beteween the measure and reference beams by flipping a mirror (or something like that).

In spectroscopy this is commonly done with light sources that consist of a deuterium lamp and a grating/slit monochromator. Since the output of the lamp varies with temperature and such, this is a good method to measure the reference beam without having to remove the sample.
 

alf638

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In my opinion you should just use an infrared thermometer, you can get them for about $20 on the internet. And yes the liquid would absorb some of the heat (I think), but it would also weaken the beam from reflection (again I think). I hope I have helped and if yes please dont hesitate to give me some reputation:)
 

Benm

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You could measure how much the liquid heats up, but i don't think thats very elegant.

Building a spectrometer as described would give much better results. You can 'zero' it with the cuvette filled with water or another transparent liquid. After that you measure only the absorption by the sample liquid, without having to worry about other factors interfering.
 

daguin

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Laser beams do NOT have any heat to "take away." The heat is created at the point of interaction with whatever material the light is striking. The heat produced by that interaction is affected by many other confounding variables as well (wavelength of light, color of material, beam focus, etc.)

At best, your proposed experiment will be measuring how much light, of a given wavelength, is passed through the different liquids.

You may also be able to measure how much different liquids will heat up when interacting with a given wavelength. This too has many potential confounding variables

You could measure the refractive index of different liquids with a given wavelength

Peace,
dave
 

DIY

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so the liquid is just basicly taking away power from the laser which in the end, takes away heat. And one more thing, How would I test what you said before,

At best, your proposed experiment will be measuring how much light, of a given wavelength, is passed through the different liquids.
 

HIMNL9

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ANY medium in which you pass a light beam, more or less, take away some power from the beam (can be reflection, refraction, absorption .....) , so, any beam passing through a medium, lost power (also just the air, if you think it in a scientifical way, take away power from your beam ..... when you see the beam, it's all light reflected and dispersed from air mist, dust and particles, so it's all power taken away from the beam, after all)

Ofcourse, more density and opacity your medium have, more power it take away.

The experiment, in that form, is not so useful, cause you need also to take in consideration reflections and refractions and absorption from the container that hold the liquid, so as reference you have to use an identical container, if you want to present it in the right way.

Anyway, i have a suggestion, if you want ..... as you know, there are some solutions and liquids that looks transparents for visible light, and totally block infrareds, as the same as there are some liquid solutions that are totally dark for visible light, and left pass infrareds .....

You can then use a green module, specifying that it emits both infrareds and 532nm green, then do tests with some different liquids, and a pair of filters, one blocking IR and one blocking visible, and demonstrate not just the drop of power through the various liquids, but also the differences with visible and IR drops ..... it may require a bit more work and research, and something reliable as light detector (a luxmeter without IR filtering ?), if you don't have any LPM, but can be an idea ;)
 

daguin

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so the liquid is just basicly taking away power from the laser which in the end, takes away heat. And one more thing, How would I test what you said before,

No it is not "basically" taking heat away. Part of the purpose of my post was to help change your mindset into reality. The filter media attenuates the power of the beam. While the perceived or measured heat at beam termination may change, the medium is not taking heat away. The way you have it stated, you are NOT testing what you say you are. This alone would make your experiment, useless.

Measuring "heat" at beam termination, in the experiment you have proposed, would be so fraught with confounding variables that any "findings" would be worthless.

You have had several suggestions for experiments that you can do with the assumed equipment you have available.

It is much easier to adapt your experiment to reality than it is to adapt reality to your experiment :tinfoil:

To do science, act like a scientist.

Peace,
dave
 




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