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Herr Professor Doctor Alex


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#1 bonanova

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Posted 07 November 2007 - 09:45 AM

He's doing what? asked Jamie.

Shh.. here he comes, answered Ian.
He's studying physics
on the Internet.
I think we should humor him, OK?

So here's yer challenges for tonight, me boys. Alex had a
strange way of smiling when he thought he had his friends
over a barrel. He was smiling now.

[1] how can you tell a raw egg from a hard-boiled egg?
[you can't break the shell or use light, heat, sound or X-rays]
[2] compared to a still day, will a round-trip airplane ride take more,
less or equal time if there's a constant wind blowing?
[a headwind one way, a tailwind the other way]

And there's more where that came from, boys ;) ... have fun.

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Vidi vici veni.


#2 niner

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Posted 07 November 2007 - 07:04 PM

Spoiler for solution

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#3 Writersblock

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Posted 07 November 2007 - 07:12 PM

[1]
Spoiler for solution


[2]
Spoiler for solution

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#4 bonanova

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Posted 07 November 2007 - 08:00 PM

clarification.

compare the round-trip air travel times with and without a constant wind.
the pilot doesn't know about schedules - kind of like real life.
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#5 bonanova

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Posted 07 November 2007 - 09:13 PM

What if the wind blew at the plane's air speed?
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#6 bonanova

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Posted 08 November 2007 - 11:20 AM

Spoiler for solution

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#7 Topher

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Posted 19 February 2008 - 09:55 PM

You're working too hard on the egg puzzle. You don't need to stop the raw egg -- it will stop on its own while a hard boiled one just keeps spinning. When you try to spin a raw egg like a top the internal friction and the sloshing of the non-homogeneous contents prevents a good spin -- so you would have to work very, very hard to do the stop & start trick (maybe an electric drill with a suitable gripper would work). No problem spinning the hard-boiled egg, though. Try it.
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#8 ReMO08

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Posted 07 March 2008 - 03:02 AM

What if the wind blew at the plane's air speed?


then that would be some mighty fast winds, and not even the insane would fly then.
We should worry more on "zomg there is 400mph winds" and less on "jeez, will this trip take longer, I need to get home"

lol
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#9 bonanova

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Posted 07 March 2008 - 09:14 AM

It was interesting to me that even in a cross wind, favoring neither leg, the trip takes longer.
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#10 Crosseyed

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Posted 07 March 2008 - 08:19 PM

Spin the egg. A hardboiled egg will spin very fast and a fresh egg will not. Or wait for the Equinox; You can balance a fresh egg on its end.
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