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Start off the new year with: Brain Teasers from Richard Feynman

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Sam Wormley

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Jan 1, 2010, 7:41:48 PM1/1/10
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Start off the new year with: Brain Teasers from Richard Feynman
http://varatek.com/scott/feynman_problems.html

And a Math Problem

What is (-2i^2)^3 / i^8 ?

Edward Green

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Jan 1, 2010, 8:00:28 PM1/1/10
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OK... I'll try a one-liner for number four: the angular momentum of
the field is _not_ zero before we cut the current to the solenoid.
According to the Poynting vector the static field has circulating
energy, and it also has circulating momentum. When we figure out how
to calculate this, we can calculate the resulting ... no we can't. We
can get an upper bound on the angular momentum of the disk after cut
off, since some of the angular momentum is presumably radiated off.

Shorter answer: solenoidal magnetic fields have intrinsic angular
momentum.

Mapsread

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Jan 1, 2010, 8:02:24 PM1/1/10
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I'll try the math: (-2 * -1)^3 / (-1)^4 = 8 / 1 = 8

Androcles

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Jan 1, 2010, 8:23:50 PM1/1/10
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"Sam Wormley" <swor...@gmail.com> wrote in message
news:iNednRX5TcrRC6PW...@mchsi.com...

> Start off the new year with: Brain Teasers from Richard Feynman
> http://varatek.com/scott/feynman_problems.html
>

Mirror, Mirror... pathetic

Train Problem... the answer is -gravity-. You think it is the conic wheel?
Take away gravity, then.

Sprinkler Problem... it sucks.

E&M Paradox...
http://en.wikipedia.org/wiki/Fleming's_left_hand_rule_for_motors

> And a Math Problem What is (-2i^2)^3 / i^8 ?

i^2 is defined as -1. The rest can be solved by a computer.
http://www.androcles01.pwp.blueyonder.co.uk/Euler.xls



Sam Wormley

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Jan 1, 2010, 8:29:47 PM1/1/10
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:-)

Uncle Al

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Jan 2, 2010, 1:56:37 PM1/2/10
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1) Coordinate inversion. Try standing on the mirror
2) Gravity. Look at mechanisms for derailment.
3) Angular momentum is an absolute arrow of time. Feynman's
sprinkler in reverse is stationary.
4) What is the closed system? Then, conservation laws. But before
all that... How does one create a magnetic field without aligning
angular momenta of particles or their orbits? Torque in, torque out.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz4.htm

Edward Green

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Jan 5, 2010, 7:07:41 PM1/5/10
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On Jan 1, 7:41 pm, Sam Wormley <sworml...@gmail.com> wrote:
> Start off the new year with: Brain Teasers from RichardFeynman
>    http://varatek.com/scott/feynman_problems.html

Allow me to express my usual disappointment that this bait did not
draw more fish. Surely _everybody_ else who reads this NG can't
either be in the category (1) doesn't have a clue how to answer them,
or else (2) thinks they are so old hat as to be too boring to discuss?

I suppose I'm leaving out a few categories.

jmfbahciv

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Jan 6, 2010, 8:41:50 AM1/6/10
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yep. I can't aitchteeteepee on my system.

/BAH

Edward Green

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Jan 7, 2010, 6:24:46 PM1/7/10
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You mean you can't click the link? You mean you are willfully using a
text only connection?

Once upon a time I thought the beauty of text only was that it could
be distributed to anybody with a 1200 baud modem and a phone line, but
I see that never actually came to pass. The whole world will have
broadband first.

eric gisse

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Jan 7, 2010, 6:57:51 PM1/7/10
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Sam Wormley wrote:

8 / 1 = 8

i to a power cycles back to +1 every 4th integer power.

jmfbahciv

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Jan 8, 2010, 10:14:25 AM1/8/10
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Edward Green wrote:
> On Jan 6, 8:41 am, jmfbahciv <jmfbahciv@aol> wrote:
>> Edward Green wrote:
>>> On Jan 1, 7:41 pm, Sam Wormley <sworml...@gmail.com> wrote:
>>>> Start off the new year with: Brain Teasers from RichardFeynman
>>>> http://varatek.com/scott/feynman_problems.html
>>> Allow me to express my usual disappointment that this bait did not
>>> draw more fish. Surely _everybody_ else who reads this NG can't
>>> either be in the category (1) doesn't have a clue how to answer them,
>>> or else (2) thinks they are so old hat as to be too boring to discuss?
>>> I suppose I'm leaving out a few categories.
>> yep. I can't aitchteeteepee on my system.
>
> You mean you can't click the link?

I can click but it would take hours to download.

> You mean you are willfully using a
> text only connection?
>

I am willfully imposing a text-only connection. I got the library.
If a mess happens, I don't have to clean it up.


> Once upon a time I thought the beauty of text only was that it could
> be distributed to anybody with a 1200 baud modem and a phone line, but
> I see that never actually came to pass. The whole world will have
> broadband first.
>

I think people should be limited to 300 baud and phone line. However,
the former disappeared with the ASR33s and latter is going to
disappear relatively soon ;-(.

/BAH

eric gisse

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Jan 8, 2010, 1:06:28 PM1/8/10
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jmfbahciv wrote:

I never fashioned you as a luddite.

You know the internet is pretty nice with images, right? Not all of it is
porn, which is also pretty nice.

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