## What are some nice modern physics experiment that I can do?

I need some modern physics experiment to be presented on science fair. I have no idea like im thinking of particle physics like atom smashers but it's impossible to create one for just a month. The cornstarch in a stereo has been gotten by others so im thinking of photoelectric i dont know, so please i need suggestions about this. thanks
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 How about a cloud chamber. They are not difficult or expensive to make and would provide a neat visual demonstration of ionizing radiation.

## What are some nice modern physics experiment that I can do?

 Quote by QuantumPion How about a cloud chamber. They are not difficult or expensive to make and would provide a neat visual demonstration of ionizing radiation.
yes I was thinking of making a cloud chamber, but I want to see some muons/ positrons. would that cost me much? and is it too long to create one?
 I saw an amazing demo a few months ago. It consisted of an upright transparent tube filled with sand. At the bottom there was an inlet for compressed air that could "bubble up" through the sand, loosening it up and essentially liquifying it. The demonstrator then took a steel ball and dropped it into the sand. It dropped right through to the bottom, you could hear it hitting the bottom of the chamber. Then he turned the air off and tapped the side of the tube a few times to make the sand settle. He then dropped an identical steel ball which just landed on the surface of the sand, not through it. Turn on the air, and boom it goes straight to the bottom. He also had a magnet on a string to fish the balls back out of the tube. The tube was about 25cm in diameter, maybe 1m high. The balls were about 25mm diameter. Apparently for this to work you need sand with very sharp-angled grains. http://www.youtube.com/watch?v=EPGIHqd8BUQ
 Blog Entries: 8 The two other pics of mine; Attached Thumbnails
 Vortex ring launcher http://www.eskimo.com/~billb/amateur/vortgen.html It is amazing how far the rings from a garbage can can travel. You can use a curtain of string hanging from a bar as detector.

 Quote by elishamei9000 yes I was thinking of making a cloud chamber, but I want to see some muons/ positrons. would that cost me much? and is it too long to create one?
A cloud chamber will detect any ionizing radiation, including muons and positrons. If you put a magnetic field in the cloud chamber than you can differentiate between positrons and electrons.

 Blog Entries: 8 Hi, I'm glad you liked it! The first crappy setup cost me nothing, as I already had the necessary stuff at home. And that setup took me an hour or so (incl. doing slits). I have done the experiment many years before with professional equipment at university, so I already had some experience. Pen lasers are cheap; 10$or so (the laser I used is a cheap, crappy one). If you have nothing at all to start with, I think you can make it with less than 20$ (laser, slits, tape/Blu-Tack, tools). A friend of mine got the idea that Lego Technic could be useful for this purpose. I bought a Lego Technic Crawler Crane (9391) for about 20\$ and tried to build an adjustable laser device out of it. But this took me some time though, since I had to figure out a workable design. It took me probably four hours or so (experimenting, building). In order to connect an external power supply to a pen laser, you'll need some tools (soldering) and basic electronics knowledge. I used a 4,5 V/300 mA adapter + one capacitor (220 μF, 50V) in parallel (for extra voltage stabilization) and a 330 Ω resistor in series (to get a proper current) + a power switch. This took me about an hour or so. But, depending on the laser and the adapter, this can take some time and experimenting in order to get a good voltage/current (not too high, not too low); the brightness and quality of the laser light is very dependent on this. It's really all up to you, how much time you want to spend and what you think you'll be able to manage. As I said, you can do a very basic experiment with a pen laser, tape/Blu-Tack and pencil leads/hair/thin copper wire, it's quite easy. I found two more videos; Double Slit Experiment with just a laser and three pieces of pencil lead www.youtube.com/watch?v=ZXyxnxnWAAQ (just the basics) Double Slit Experiment (How to do it at home) http://www.youtube.com/watch?v=vsQ3YTJqyOY (he got better patterns than me; it seems his laser was better than mine and that he used a nice, really dark environment) But I think a cloud chamber would be quite cool too; I got inspired and will probably try that out sometime . Anyway, I wish you good luck!