[QUOTE]in the bowels of the Westin St. Francis hotel on Union Square, Rob Holsen washes the hotel's money[/QUOTE][URL="http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/12/27/MNHU1GT8K4.DTL"]http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/12/27/MNHU1GT8K4.DTL[/URL]

[QUOTE=only_human;243878][URL]http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/12/27/MNHU1GT8K4.DTL[/URL][/QUOTE]
Isn't money laundering illegal?:whistle:

[QUOTE=EdH;244136]Isn't money laundering illegal?:whistle:[/QUOTE]Californians have more freedom to do/grow/wash things in their basements than most other folks.

If I dug a hole through the earth....
 

[url]http://www.ubasics.com/dighole/[/url]

[URL]http://amasci.com/amateur/traffic/trafexp.html[/URL]

[QUOTE=Xyzzy;245656][URL]http://amasci.com/amateur/traffic/trafexp.html[/URL][/QUOTE]
Wow! Another amazing "new" discovery, I've been doing for years...

[URL]http://www.youtube.com/watch?v=m1dv_y_3EK0[/URL]

[QUOTE=cheesehead;206455][url]http://www.wired.com/geekdad/2010/02/leftover-valentines-chocolate-use-it-to-measure-the-speed-of-light/[/url][/QUOTE](This link that I'm replying to was posted just after valentines Feb 23rd 2010; it has a science experiment in a microwave using leftover holiday chocolate) I just looked at the link and felt like bumping it up for its' coolness factor.

I'm really surprised that one can estimate the speed of light using a microwave this way!! I thought that the magnetron's radiation was splashed all over the place by a fan to distribute the radiation more evenly and would have expected that to make results difficult to interpret. This experiment reminded me of a two day tourist tour I took from Hong Kong (prior to British turn-over) into mainland China.

One stop was a zoo. Back then I received a quick education that China had no trouble understanding enterprise and money earning. Among the things that I did at that zoo that cost a little extra money was dip my hands into a small tin basin of water and then rub my hands on two protruding handles. This made standing waves that had pretty peaks that splashed droplets upward.

Another thing I did at that zoo was lift up a crocodile to have a picture taken by a friend that accompanied me. I was squatting and ready to jump aside and very nervous. I was well aware that risks and liabilities had different metrics there. My friend was doing translating for me but she was holding the camera at some distance. I really, really wanted some reassurance about risks but couldn't communicate with the reptile wrangler. Thus it isn't that dramatic of a pose. Maybe I will post the photo some day if I come across it again.

[QUOTE=only_human;246520](This link that I'm replying to was posted just after valentines Feb 23rd 2010; it has a science experiment in a microwave using leftover holiday chocolate) [/QUOTE]

I agree this is cool. I'm planning on doing this with 20 teenagers on Wednesday night. I've been building up to this in the hope some of them will understand it.

The first week we measured the speed of rope. I set up a standing wave in a rope and we measured the wavelength with a tape measure, and counted the cycles while somebody marked 10 seconds against a clock. Included some pretty pictures of a wave and its reflection canceling to explain how the standing wave was related to the movement of the wave. The speed of rope turned out to be 45 ft/sec.

The next session we reviewed the previous session then had a discussion about how microwave ovens work.

Why does the coffee get hot but not the cup (at least directly)?
Because microwave ovens heat water molecules

What, scientifically, is water? (Everybody knew H2O.)

Since all water is H20, what is the scientific difference between hot water and cold water? (Nobody knew hot water molecules move faster)

How do microwaves heat water? Nifty visual aid for this, consisting of a washer on a string taped to piece of cardboard. Moving a magnet below the cardboard gets the washer swinging around. Said "if I was fast enough, I could have the magnet back here just as the washer swings around, and boost it again. Water molecules are little magnets and that react like this to the electomagnetic waves, making them move rapidly - and rapidly moving H2O is hot water.

Why do microwave ovens have rotating trays? Because of hot spots.

Why do microwave ovens have hot spots? Standing waves. The microwaves bounce back an forth in the oven and interact just like our rope, causing places where they move very little and places where they move very much. You get very hot water in the large movements, and only warm water in the slight movements - all related back to the rope's standing wave.

This week we will review all of that, then point out we can find the wavelength from the standing wave and the look up the frequency of a standard electronic part, and calculate the speed of microwaves. I'll need a bit of handwaving to argue all electomagnetic waves, including light, have the same speed.

There are many nitpit opportunities in this - I already know many of them. But it's close enough to right and will capture some of the kids imagination. And all them will like the ice cream with melted chocolate.

William

[QUOTE=wblipp;247137]I agree this is cool. I'm planning on doing this with 20 teenagers on Wednesday night. William[/QUOTE]

Yep. A good frying in the microwave will probably improve
their minds considerably.

David

PS If that doesn't work, suggest they try posting
their latest brainwaves on number theory to Bob ;)

[QUOTE=wblipp;247137]I agree this is cool. I'm planning on doing this with 20 teenagers on Wednesday night. I've been building up to this in the hope some of them will understand it.
[...]
This week we will review all of that, then point out we can find the wavelength from the standing wave and the look up the frequency of a standard electronic part, and calculate the speed of microwaves. I'll need a bit of handwaving to argue all electomagnetic waves, including light, have the same speed.

There are many nitpit opportunities in this - I already know many of them. But it's close enough to right and will capture some of the kids imagination. And all them will like the ice cream with melted chocolate.

William[/QUOTE]Sounds like a good learning experience that many will enjoy and remember. Perhaps include a soupçon of dimensional analysis with that tasty dessert. I didn't get dimensional analysis presented to me in a coherent way until a college chemistry class but surely earlier is better, especially with all that physics being discussed.

I have high hopes for the current crop of curious juveniles. For one thing, unlike my generation, the Harry Potter novels have ensured that they aren't intimidated merely by the thickness of a book.