Ideas for a Science Fair project?

[Jimmymcjimthejim]

Any good ideas for a science fair project involving lasers? (For school)
I was thinking of like
What color absorbs violet light the best?
And I would test this using a violet laser on a balloon, and the balloon that pops the fastest would absorb violet light the best.
Any ideas are appreciated.
Thanks,
Jimmymcjimthejim

Oh, and keep in mind that I have to use the Scientific method to test it, so no crazy stuff please.

 

[maxkillz]

On the color wheel yellowish green is the opposite so i would say a yellow balloon would be the best ;D ;D

 

[RA_pierce]

How about you make a Home security system.

Set up a laser beam as a sensor, so that when someone or something interrupts the beam, a >50mW pulsed green laser blasts you in the face along with a 100mW blu-ray, a 200mW red (all unfocused of course, and spinning in confusing patterns) and a huge flood lamp. Then you get hit with a barrage of paintballs (or some kind of high velocity projectile). And of course you have to have a very loud siren.

If you set this up in front of your door, and someone breaks in, they get hit by a bunch of crazy things at once. It would be very disorienting and it would draw a lot of attention.
It's like a security system.

Or you can just make it so when the laser sensor is tripped, a massive tesla coil is activated and kills anything within a 5 meter radius.

A+ for sure.

 

[Jimmymcjimthejim]

How about you make a Home security system.

Set up a laser beam as a sensor, so that when someone or something interrupts the beam, a >50mW pulsed green laser blasts you in the face along with a 100mW blu-ray, a 200mW red (all unfocused of course, and spinning in confusing patterns) and a huge flood lamp. Then you get hit with a barrage of paintballs (or some kind of high velocity projectile). And of course you have to have a very loud siren.

If you set this up in front of your door, and someone breaks in, they get hit by a bunch of crazy things at once. It would be very disorienting and it would draw a lot of attention.
It's like a security system.

Or you can just make it so when the laser sensor is tripped, a massive tesla coil is activated and kills anything within a 5 meter radius.

A+ for sure.

Lol, great project (and kind of useful!)
But I don't see how it can be used for the science fair using the scientific method.. There's nothing to prove there with that project!

 

[diachi]

You could demonstrate how different colours of light are refracted more, or absorbed more, and explain about energy densities.

 

[RA_pierce]

Get several different types of flowers, get a decent spectrum of lasers (IR, red, green, Blu-Ray) at relatively high power levels and see how they react to different colors of light. You can make a green house type thing.

Stick the flowers in complete darkness (except for the laser light) and see which wavelength can support photosynthesis best.

It sounds pretty original and I actually wanted to do it for a science project myself. But I've graduated already.

And if you can't get enough power out of lasers alone, get IR, red, green and near UV leds and couple them with the lasers.

 

[Jimmymcjimthejim]

You could demonstrate how different colours of light are refracted more, or absorbed more, and explain about energy densities.

Interesting. I like this because not many people have different color lasers, but I don't like how you don't really need lasers to do this. Good idea though.

Get several different types of flowers, get a decent spectrum of lasers (IR, red, green, Blu-Ray) at relatively high power levels and see how they react to different colors of light. You can make a green house type thing.

Stick the flowers in complete darkness (except for the laser light) and see which wavelength can support photosynthesis best.

It sounds pretty original and I actually wanted to do it for a science project myself. But I've graduated already.

And if you can't get enough power out of lasers alone, get IR, red, green and near UV leds and couple them with the lasers.

Good idea! But, again, the only thing that I don't like about that experiment is how it doesn't have to be laser specific.

 

[RA_pierce]

Good idea! But, again, the only thing that I don't like about that experiment is how it doesn't have to be laser specific.

Well, that can be a different experiment. You can use a full spectrum of lasers Vs. a full spectrum of LEDs. You can see if coherent/monochromatic light is absorbed better than incoherent light.

Umm.. what else... How about constructive and destructive interference?
or... Make some sort of communications device using lasers and pit it against a more conventional means of communication.
But that sounds a little intense.

 

[VillageIdiot]

I still reckon thermal experiments with balloons is the coolest.

Do:

different colours on different balloons,
pop an opaque baloon inside a clear balloon,
explain why you need to focus the laser,
why a red laser won't pop a red balloon or a white balloon,
and why a blu-ray can pop lots of different colours.

 

[Jimmymcjimthejim]

I still reckon thermal experiments with balloons is the coolest.

Do:

different colours on different balloons,
pop an opaque baloon inside a clear balloon,
explain why you need to focus the laser,
why a red laser won't pop a red balloon or a white balloon,
and why a blu-ray can pop lots of different colours.

Sounds good, except for the fact that I don't have a red (diode) balloon popping laser. But maybe I can convince my parents to let me get one if this experiment goes well.

 

[pullbangdead]

I personally like the differing index of refraction for different wavelengths of light, and calculating the indices of refraction of a prism. Lasers make it really easy to measure using a prism and a decent little test setup. Real math, real physics that affects people every day. And for all the non-physics judges who think they have better things to do than read all your work and equations, it's "Oh, so this is how rainbows are made, but with LASERS!!!1!". I could send you a bunch of stuff to get started, we did a lab like that in my undergraduate program with multiple laser colors and prisms. It was more intense, but it would be really easy to scale back into a great high school science fair project.

 

[Jimmymcjimthejim]

That sounds awesome! It would be a little more interesting and applicable than the balloon popping thing also. If my science teacher doesn't like balloons, then I'll do that instead.

 

[nikokapo]

i agree with both VI and pullbangdead

refraction and some colour tech stuff would be great

also, i'd add the fluorescence phenomenon with a blu-ray


A++ guaranteed.


if not, just lemme call Chuck

 

[HumanSymphony]

i actually think a laser alarm system would be pretty sweet. I'll probably do it myself for fun lol ;D all you'd need is a photo diode connected to a super loud alarm type thing. Shine laser directly on photo diode. When light is shined on it the diode has maximum resistance. When you interrupt beam there's no resistance = alarm goes off granted there's no light in the room either lol

 

[Jimmymcjimthejim]

i actually think a laser alarm system would be pretty sweet. I'll probably do it myself for fun lol ;D all you'd need is a photo diode connected to a super loud alarm type thing. Shine laser directly on photo diode. When light is shined on it the diode has maximum resistance. When you interrupt beam there's no resistance = alarm goes off granted there's no light in the room either lol

Yes, that is useful, but there's nothing to prove :-/

 

[HumanSymphony]

[quote author=HumanSymphony link=1220125783/0#13 date=1220388982]i actually think a laser alarm system would be pretty sweet. I'll probably do it myself for fun lol  ;D all you'd need is a photo diode connected to a super loud alarm type thing. Shine laser directly on photo diode. When light is shined on it the diode has maximum resistance. When you interrupt beam there's no resistance = alarm goes off   granted there's no light in the room either lol

Yes, that is useful, but there's nothing to prove  :-/[/quote]
You can prove that um the uh photo diode works!