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Make a cereal box spectrometer (I recommend using a piece cut from a sheet of plastic diffraction grating) and use it to look at the spectrum of a compact fluorescent lamp. Here's a table of mercury's spectrum. If you can see lines with wavelengths shorter than the 404.6 nm line then you can see UV. The 404.6nm line is on the far left. Seeing the 398.39 nm line might not count because it is so close to violet. If you can see the lines around 365 nm, then you can definitely see UV; however they may be too dim to see even if your eyes are able to detect those wavelengths.

http://scitoys.com/ lots of great activities and kits here

http://scitoys.com/

I did this one with my daughter for a science fair project. For me, the parts DID cost more than $5, but there were a lot of things I bought singly, but would have the cost lowered spread out over multiple applications; bag of rubber bands, one long piece of PVC, wood, nails, etc...Also many pieces can be brought from home to lower the cost.

While the results were never that spectacular, given more time, and less baling wire construction, it might be fun and educational. You can throw in lessons about resistors and capacitors then use it to power something bigger.While it won't help much for logic gates, you gotta start somewhere.

How to build a generator

Check out scitoys.com for some ideas. The section with a radio is pretty darn cool, and he does have a few simple projects like a 1-Watt amplifier and a laser audio transmitter. No soldering needed, which is a plus for a school setting with 9th graders.

steveha

I've seen a number of solar cell projects that don't use silicon. One that uses oxidized copper plates and salt water and another that involves titanium dioxide. http://scitoys.com/scitoys/scitoys/echem/echem3.html#flatpanel

Hey, I can do better than that. I can "build" my own solar panels for just the cost of a crowbar and a ladder by ripping them off my neighbor's roof and then soldering new wires to them.

Lame article. Wake me when someone actually makes their own solar cells at the $/W of a commercial unit.

This web site is perfect for inquisitive teens:

http://scitoys.com/

It's crazy cool. He shows you how to make your own working spectroscope with a box, a CD, two razor blades, and some tape!

The guy who put up that site has written some actual paper books, so you could give one or more of those. Or, just order some magnets and diffraction gratings and such for building the gadgets, from the catalog:

https://www.scitoyscatalog.com/

I really wish I could have had access to that web site when I was 13. Oh, well... at least I have access now!

steveha

Google is being of limited help here. The main link I'm finding is to Liquidmetal Technologies, which is producing Liquidmetal and Vitreloy -- zirconium-based alloys which are amorphous in structure (hence the "liquid" in the name) but are otherwise solid in appearance and use (and much stronger than stainless steel or titanium). This is not something one would be pumping through heat tubes to cool a CPU.

Obviously, mercury is out due to its toxicity. My initial thought was they're using metal bits in a suspension, but I have doubts as to whether this would actually do anything useful. Deeper searching yields this page, which describes a gallium/indium/tin alloy which is liquid at room temperature. Wikipedia'a entry for gallium concurs, saying, "It has been suggested that a liquid gallium-tin alloy could be used to cool computer chips in place of water."

Any materials experts out there care to comment?

http://scitoys.com/

This web site is full of cool stuff you can build. Available in dead-trees versions if you prefer. Seriously, check this out; this site makes me want to start building things.

Example: build a home-made radio. He starts with a trivial radio with only two parts, then adds another part to improve it, then improves it again... eventually he has you rolling your own capacitors! Each step illustrates something cool. By the end you are building a crystal radio like the ones soldiers used to build during World War I.

steveha

I liked your homepage, you seem to be really interested in Nanotechnology and the likes. You need to understand more of the underlying science though, that will help you to understand how things fall into place. It is too easy to get fascinated with a bunch of hype technologies and popular science attached to it. All of it comes with a long history of development that is required to understand the merits and how things work. Most of this is hidden to the casual passer by. I guess university is going to do that for you.

If you really want to build a semiconductor/"Nanotechnology" device at home I would suggest to look into solar cells. There is a type of cuprous oxide/electrolyte cell that can be very easily manufactured. (eg here http://scitoys.com/scitoys/scitoys/echem/echem2.html) Also look for graetzel cells.

I used to check out http://freshmeat.net/ almost daily, but that was when I was only a few years into Linux and still on an endless search for software that did different things, and at the time it seemed simpler to just wait and see what came up on fm every day (you could easily tell how active things were that way, too). Speaking of fm---does anyone have a copy of that old butchered-meat logo fm used to have, waaaay back, before the beginning of the fm II theme?

About weekly, I'll check out http://amasci.com/ (amateur science and electricity stuff), http://en.wikipedia.org/ (duh), http://www.cray-cyber.org/ (free supercomputer access), http://www.hpcalc.org/ (HP48/49/etc calculator stuff), etc., to check for new stuff. I'll check my http://facebook.com/ and http://myspace.com/orangesquid (shuddup) messages about weekly. From time to time I might browse http://www.amazing1.com/ (catalog which has Tesla coils and stuff, though they're not actually the best place for parts/kits/devices) or search for scientific equipment or old unix systems on http://www.ebay.com/ (see the Used SGI Buying Guide FAQ, etc).

I also check up on some of my friends via http://os.livejournal.com/friends every few days.

Lately I've been choosing a new section on http://scitoys.com/ to read every few days. Every few weeks, I'll usually find a different information-type site to read through gradually, or pick a topic to research on wikipedia.

Well, a little googling turned up this which seems to explain it better without of the nasty physics technobabble. And this is how to do it yourself.

Cool stuff indeed.

http://www.scitoys.com/scitoys/scitoys/thermo/liqu id_metal/liquid_metal.html

...which melts at an even lower temperature

See also:
http://www.scitoys.com/scitoys/scitoys/thermo/liqu id_metal/liquid_metal.html
( kudos to venkeroz on tweakers.net for that link in a post on this story 4 days ago )

http://www.scitoys.com/scitoys/scitoys/thermo/liqu id_metal/liquid_metal.html

> it is probably a gallium alloy

Or some other weird alloy. You can buy "liquid metal" for fun at http://www.scitoys.com/scitoys/scitoys/thermo/ther mo4.html . They even claim it is nontoxic (no cadmium or mercury).

But I still wonder what this has that water does not? :-) Cooling wise, I mean.

To placate the handwringers, we called it a 'Linear Accelerator' instead of a railgun or Gauss Rifle. Can't have those dangerous 'weapons' in school.

If it changes density on 'freezing' that will cause distortions, probably bad enough that the surface is no longer very reflective. I tried it with wax once, and the main problem was that the edges froze first, which caused ripples in the rest of the surface.

There's also a not-very-toxic alternative to mercury for anyone who wants to try building a small LMT; Gallium/Indium/Tin alloys which are liquid at room temp.

http://www.scitoys.com/scitoys/scitoys/thermo/liqu id_metal/liquid_metal.html

all kinds of little projects, some electronic, some otherwise. My son(13) is doing the Gauss Rifle. So as not to freak out the teacher, we're calling it a 'Linear Accelerator', instead of a railgun.

all kinds of little projects, some electronic, some otherwise. My son(13) is doing the Gauss Rifle. So as not to freak out the teacher, we're calling it a 'Linear Accelerator', instead of a railgun.

Think of this and then imagine rows and matrices of deuterium atoms, millions long, lined up on the surfaces of palladium, tugged different ways by electrical current. Those last few atoms on the end of a row might be moving pretty fast.

Yes, but think of the scale here. On the atomic level, it may be possible to have tiny, localized areas where particles can be accelerated to very high speeds. Granted, it would be extremely rare and definitely not generate energy on the scale of hot fusion, which basically depends on having a "nuclei soup".

How could we get a massive acceleration using only objects that repel each other? This is an interesting experiment: http://www.scitoys.com/scitoys/scitoys/magnets/rin g_launcher/ring_launcher.html. Only a small force is actually added to each element, but the whiplash effect accelerates the last object to high speeds. What if the forces between palladium and deuterium are such that the deuterium atoms are arranged in straight rows and matrices on the surface of palladium? And what if the applied electrical current tugs each atom slightly, which when released allows a cascading whiplash effect on rows millions of atoms long? Pure conjecture, but it illustrates a mechanism by which a few atoms might be accelerated to very high speeds, and in a somewhate accurate linear way (as opposed to hot fusion which hopes for accidental collisions between randomly moving nuclei).

Build your own railgun Today! Kids love this one!

Learning is made easier with immediate results that make students wonder 'Why? How?' Otherwise, it's dry, boring, and students don't learn anything. They memorize what they'll need just long enough to pass the test and then forget it.

While I know your post was a joke, it got me thinking. Maybe you could get a whole bunch of these kits together and make a graphite puck and you might have one.

Here is another experiment to convince yourself:

A magnetic levitation device.

Gravity provides a constant downward force of 9.8m/s^2, the magnets provide a constant upwards force of 9.8m/s^2, the result? The graphite floats. Unless you believe that energy can come from no where, you have to accept that the magnets are providing the energy for the upward force. Eventually they'll fail, like all batteries, and have to be recharged by remaking them, but that doesn't stop them from being useful as an energy storage device.

No one is claiming they are getting free energy. It's just a great way to tap it. Another way to put this in perspective is a Fission generator. It takes a LOT of energy to make Uranium for a reactor, however, in the end, the high energy density, and readily available uranium, makes it a good combination for fuel plants.

Are you claiming that you can extract energy from a magnet when that energy was not there in the first place? You should read the physics page where the 'ball bearing shooter' was analyzed. You'll find that the act of placing the magnets and ball bearings in position provides energy to the machine. The act of rolling another ball into the first magnet pushes it just outside it's equilibruim, and it releases the energy stored when the balls were placed.

This is all well and good, and applies to his motor - a bunch of magnets are placed at a point just before they release a bunch of energy. Here's the fun part --> He is claiming that the magnets return to that magic equilibrium point by themselves at the end of their cycle. Then it only requires another tiny push to set them off again, and again releasing a huge rush of energy.

The ball bearing gun, however, does not return to it's previous equilibrium. In fact it provably enters a state of much lower energy than the state it started in.

The motor that as described is a classic perpetual motion machine. It may be that the article is incorrectly describing the motor, and perhaps he has produced an ultra efficient motor. However, saying that any apparatus has "315%" efficiency (ie, output > input) is just begging for a full detailed analysis.

And, by the way, the ball bearing gun uses the pattern of magnet-ballbearing-ballbearing space magnet-ballbearing-ballbearing space, etc. Not alternately bearing, magnet, bearing, magnet. This is important for the operation of the device - read the article if you don't understand why. Just keep reminding yourself that the end result contains less energy than the beginning state.

-Adam

http://www.scitoys.com/scitoys/scitoys/magnets/gau ss.html

I tried several experiments (and I don't even have kids, I just like to do this kind of stuff and I'm either too lazy or stupid to come up with my own stuff) and it's just fun to do... For us geeks, the site includes an argumantation of why a certain device works and how with the laws of physics and all...

scitoys.com

I haven't seen this posted yet, and even as one of legal drinkin' age, I still steal an idea here and there from it: SciToys

http://www.scitoys.com/ Lots of information on this site.

At 400 Mbps, even a QAM256 signal would be blinking too fast for even the most Jolt-enhanced epileptic.

If you would like to do this yourself for a few dollars, there is a laser communication project here that uses a pocket laser pointer to send voice signals over 8 miles.

I am currently modulating a laser pointer at 28.322 Mhz a few feet away from where I sit. It can go faster, but my receiver circuit maxes out at about 30 Mhz (it uses a $5 photodetector).

The goal is to make a WiFi speed link (13.2 Mbps actually) that will go a few miles using cheap parts (under $20 per node). I'll put the details up on my web site when it's ready.

This is a neat site, probably mentioned in other comments but a quick scan does no reveal, so ...

scitoys.com is a nifty site with a lot of hands-on science experiments.

timothy

Kids getting arrested for science fair projects that frighten the principal are too common.

This kid had to hire a lawyer to get his suspension redacted from his permanent record.

He said he was going to build a Plastic Hydrogen Bomb from plans on the Internet, and that his parents were buying him the parts. The principal had his house searched by the police.

The plans were included in the police report.

Kids getting arrested for science fair projects that frighten the principal are too common.

This kid had to hire a lawyer to get his suspension redacted from his permanent record.

He said he was going to build a Plastic Hydrogen Bomb from plans on the Internet, and that his parents were buying him the parts. The principal had his house searched by the police.

The plans were included in the police report.

As a kid I loved the Edmund Scientifics catalog (thanks to my grandparents) and guess what... they do indeed have a website.

I spent a total of five minutes and found gyroscopes, gears, pulleys

If ES is too high-tech, there's a great site dedicated to "Science Toys You Can Make wWith Your Kids". Instructions on building kaleidoscopes can be found there.

Oh hell, or just look here

About as useful as the Plastic Hydrogen Bomb.

For a discussion of cheap ways to do photography and video through a microscope, try

Photography through a miscroscope

We are in complete agreement.

When I built my first computer back in the very early 1970's, the computer I used while pursuing a PhD in biochemistry was a mainframe. It cost me six or seven thousand dollars to build my tiny computer, and a lot of soldering and research.

It is now a "generation" later. We have tools to let novices write programs that would have astounded teams of programmers back then. We have script kiddies attacking government and industry computers. Things move quickly, and ever more so.

One of the reasons that a small lab costs $50,000 (small change to a drug dealer) is that the goals are different. An amateur would not be as interested in careful controls, and could simply buy viruses that insert transposons and freely mix two genomes, and test any viable result for the expression of the cocaine gene. Perhaps a radish was the wrong thing to pick -- a yeast is easier to culture and grow (ask an amateur beer maker).

But some labs are cheaper than others. A suicide terrorist could take blood samples containing several deadly human diseases, and inoculate a pig with those and a virulent flu virus, and hope for a deadly contagious recombination to occur, perhaps aided by some drugs or viruses that make recombinations more likely. He doesn't care about isolation procedures -- he is hoping it will kill him.

But I am expecting science fair projects that insert new genes into yeast to be in high schools in my lifetime. The same high schools that produce kids that build bombs and shoot automatic weapons in cafeterias.

I am in the business of teaching kids how to do science on a shoestring. I get mail from frightened parents who think my Plastic Hydrogen Bomb project is really teaching kids how to make thermonuclear weapons (it is really just a high-tech squirt gun). I also get a lot of mail from people interested in scaling up my Gauss Rifle to lethal energies.

I am very careful how I answer these people.
I like to think that by channelling their energy into building toys, I am refocussing their aims to less destructive pursuits. But as much as I would love to help the next Einstein or Edison, I am careful not to help create the next Bin Laden.

We are in complete agreement.

When I built my first computer back in the very early 1970's, the computer I used while pursuing a PhD in biochemistry was a mainframe. It cost me six or seven thousand dollars to build my tiny computer, and a lot of soldering and research.

It is now a "generation" later. We have tools to let novices write programs that would have astounded teams of programmers back then. We have script kiddies attacking government and industry computers. Things move quickly, and ever more so.

One of the reasons that a small lab costs $50,000 (small change to a drug dealer) is that the goals are different. An amateur would not be as interested in careful controls, and could simply buy viruses that insert transposons and freely mix two genomes, and test any viable result for the expression of the cocaine gene. Perhaps a radish was the wrong thing to pick -- a yeast is easier to culture and grow (ask an amateur beer maker).

But some labs are cheaper than others. A suicide terrorist could take blood samples containing several deadly human diseases, and inoculate a pig with those and a virulent flu virus, and hope for a deadly contagious recombination to occur, perhaps aided by some drugs or viruses that make recombinations more likely. He doesn't care about isolation procedures -- he is hoping it will kill him.

But I am expecting science fair projects that insert new genes into yeast to be in high schools in my lifetime. The same high schools that produce kids that build bombs and shoot automatic weapons in cafeterias.

I am in the business of teaching kids how to do science on a shoestring. I get mail from frightened parents who think my Plastic Hydrogen Bomb project is really teaching kids how to make thermonuclear weapons (it is really just a high-tech squirt gun). I also get a lot of mail from people interested in scaling up my Gauss Rifle to lethal energies.

I am very careful how I answer these people.
I like to think that by channelling their energy into building toys, I am refocussing their aims to less destructive pursuits. But as much as I would love to help the next Einstein or Edison, I am careful not to help create the next Bin Laden.

While that hasn't been my experience, all you really need is a way to tell the difference.

If the static goes away and the radio gets quieter for a moment, that is still a fine indication of the meteor.

And of course you can simply invert thr graph to make these look like peaks instead of notches.

I'll post my results at the Scitoys message board.

My kids (6) were fascinated with this science project.

We also tried the Binaca cannon. (The kids also went nuts with Ace Ventura jokes :-/ "[Cough] Do you have some Binaca?")

And, yes, my homeowner's insurance is rather pricey...

My kids (6) were fascinated with this science project.

We also tried the Binaca cannon. (The kids also went nuts with Ace Ventura jokes :-/ "[Cough] Do you have some Binaca?")

And, yes, my homeowner's insurance is rather pricey...

How about this? It's amazing what you can do with just a few carefully placed permanent magnets... look, ma, no electricity!

Here are a few different Gauss Guns, including the one from Half Life!

Yes, I did just pilfer these sites from Google, but didn't see any other references linked so far, soooo.....

I grew up at a great time to be a science nerd, I remember fondly the Time-Life Science Books, newspaper articles and television coverage of the Apollo missions, playing with a chemistry set...

I'm not sure what science kids resources on the net will live up to those standards. A couple that I like are Nine Planets and Science Toys you can make with Your Kids, anybody got any others?

Yeah, you can take LEDs and solar cells to transfer sound. Check this link out: http://scitoys.com/scitoys/scitoys/light/light.htm l#laser_communicator

Orange

The whole site is cool, browse around. I love the hydrogen bomb (chemical not nuclear). The levitating magnet's cool too. Now, to build that gun...