Van de Graaff Confetti Explosion

[upstateNYcuties]

So, how was the cleanup?

[JeffersonLab]

@upstateNYcuties Annoying. Some of the confetti got stuck on the ceiling and slowly rained down over the course of a week.

[LoganVideo12TV]

I wish i had some liquid nitrogen!

[Teankun]

You can also do it with styrofoan peanuts

[Connor8822]

Those are called Chads :D

[pictureperfect971]

Thanks, this was so helpful for one of my Biology projects:-) Great video, love you guys, and super cool experiment!!

[JPortfolio]

awesome application!

[Almontmarine]

Guess you kinda made a great mess. And did Steve really eat one?

[JeffersonLab]

@Almontmarine Yeah, this was one of the messier ones we've done. One actually did go into Steve's mouth.

[moh199702]

Why do u guys keep touching it with the metal rod

[JeffersonLab]

@moh199702 We aren't actually touching the dome with the nails, we're just pointing the nails at the dome. We're doing this to remove some of the charge from the dome. The paper disks would eventually form little 'fingers' rather than fly off. You can see them doing this if you watch the video carefully. By removing some of the charge, these structures would fall apart and the disks would begin to fly off again.

[mamonsin]

whats the wattage?

[JeffersonLab]

@mamonsin Of the Van de Graaff itself? I've never measured it directly, but I would guess that it's in the 60 Watt range. The motor is rated at 1.2 Amps at 115 Volts, which means it would be drawing 138 Watts, but it isn't being run full out. So, figure that ~140 Watts is an absolute upper bound. The actual power draw is probably a fair amount less. If it and my meter get in the same room at the same time sometime soon, I'll measure it.

[mamonsin]

@JeffersonLab I'll create my own. Thankyou.

[MegaTories]

@JeffersonLab I appreciate you were talking about upper bounds, but the motor's low power factor may reduce this yet further. Also, for low enough power factor, the maximum mains power draw may not be at full motor power, as adding series resistance can increase the in-phase current component.

[mamonsin]

does that van de graaff uses more electriticy than it creates?

[JeffersonLab]

@mamonsin Yes. Conservation of energy tells us that, at best, all we can do is break even. But, since this isn't a perfectly efficient machine, we end up requiring more electricity than can be produced.

[mamonsin]

@JeffersonLab i guess it would be better to have a bicycle to make it work :p

[519mac]

Two things, was this for scicast and also, try placing a car battery on the bottom, blew up our science LAB Lol

[JeffersonLab]

What is scicast?

[JeffersonLab]

Google is my friend.

No, we didn't make these videos for SciCast. We aren't in the UK, so we aren't eligible for their contest. Also, they want you to send them your videos on physical media. Actual tapes or disks. In envelopes. Using stamps. Strange...

[bmwsux4]

cool! you juat found a new way to make jiffy pop!

[blububa16]

hey thanks do you know how else you can do sparks?? really thanks you help me a lot!

[JeffersonLab]

Go into a dark room with a roll of masking tape. Wait a few minutes for your eyes to dark adapt. When you are ready, quickly pull the tape from the roll. You should see some blue-white sparks where the tape is leaving the roll.

[yesimstuntdude]

I've also heard that if you take a "Wintermint" lifesaver candy into a dark room and crack it in half with your teeth in front of a mirror it looks like it produces cobalt blue sparks. Hmm...

[blububa16]

hi i need an experiment for my science fair and im talkin about thunderstorms. i want something cool but nothing too expensive. can you guys help me out?? thanx oh and really cool show. :D

[JeffersonLab]

You could try making a thing called 'lightning bells.' It's a device invented by Ben Franklin that warned him when lightning was in the area. You'll have to Google it for more details. I wouldn't try it with an actual thunderstorm, but you might be able to get one to work by charging a piece of PVC pipe with your hair.

You could also make a plastic electroscope and then use to to see what charge different items have (positive or negative).

Good luck!

[mastashnr1]

why did you touch it?

[JeffersonLab]

We aren't actually touching it. We're holding nails and are pointing those towards the dome. We're doing that because the paper disks didn't fly off like they did during testing. They would form little 'fingers' and the charge would apparently leak off of them. You can see some of these 'fingers' near the end when the camera zooms in. Pointing nails at it removes a lot of charge at once, the papers relax, the fingers fall apart, and the disks start jumping off again when we take the nails away.

[mastashnr1]

Yes, I understand now, indubitably necessary. So you knew that it might happen?

[JeffersonLab]

Yep. After the 3rd or 4th take, it became real obvious that it wasn't going to do what I wanted it to do. Very annoying, especially after it had worked beautifully in an earlier test run. One without cameras or witnesses, of course. At least we got a lot of blooper material out of it. That, and I became very proficient at cleaning little paper disks off the floor.

[Freakk600]

Interesting i want to try that with my van de graaff now