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OT: math question

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Able2fly

OT: math question

I'd hoped that the responses would be far more interesting than merely
"looking up" the answer, and I was NOT disappointed. Thanks, all!

Bill K3UJ
================================================
> > > -----Original Message-----
> > >
> > > How would one calculate the amplifier gain (in dB) required to go
> > > from one
> > > power level to another? For example from 5W to 100W.
> > >
> > > K3UJ

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Dan Barker

RE: OT: math question

I ran into a brain-teaser once, that had me baffled for hours (I won't say
how many). Finally, I called my sister, the Rocket Scientist ("actually,
we're not _Rocket_ scientists" - That's a quote from her husband) and asked
her.

She and Paul spent a few minutes on the problem, figured it out, but it was
such a trivial answer they threw it away. Since I'd spent so long on the
Question, I gave her about a week and then I called back. Luckily they'd not
taken out the trash, so she easily found their notes and read them to me.

I won't spoil it for you 'crafters.

Dan / WG4S / K2 #2456

Problem: An alley has a 20-foot ladder across it, in the left lower corner
and leaning on the right wall. There also is a 30-foot ladder, from the
right lower corner leaning on the left wall. The laders cross at 10 feet
high.

How wide is the alley?

Usual conventions: alley is all right angles, ladders have no thickness nor
bends, blah blah blah...

This should make some juices flow out there. Just simple geometry, or is it?

PS: Iteration is cheating. Sorry Issac.

<snip>
the responses would be far more interesting than merely "looking up" the
answer
</snip>

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S55M

Re: OT: math question

Yes math is beautifull (callculating needed space for 3d antennas HI.
But google can spare some time and paper.

:)
http://home.att.net/~numericana/answer/algebra.htm#quartic

----- Original Message -----
From: "Dan Barker" <[hidden email]>
To: <[hidden email]>; "Elecraft" <[hidden email]>
Sent: Wednesday, March 30, 2005 10:22 PM
Subject: RE: [Elecraft] OT: math question

> I ran into a brain-teaser once, that had me baffled for hours (I won't say
> how many). Finally, I called my sister, the Rocket Scientist ("actually,
> we're not _Rocket_ scientists" - That's a quote from her husband) and
asked
> her.
>
> She and Paul spent a few minutes on the problem, figured it out, but it
was
> such a trivial answer they threw it away. Since I'd spent so long on the
> Question, I gave her about a week and then I called back. Luckily they'd
not

> taken out the trash, so she easily found their notes and read them to me.
>
> I won't spoil it for you 'crafters.
>
> Dan / WG4S / K2 #2456
>
> Problem: An alley has a 20-foot ladder across it, in the left lower corner
> and leaning on the right wall. There also is a 30-foot ladder, from the
> right lower corner leaning on the left wall. The laders cross at 10 feet
> high.
>
> How wide is the alley?
>
> Usual conventions: alley is all right angles, ladders have no thickness

nor
> bends, blah blah blah...
>
> This should make some juices flow out there. Just simple geometry, or is
it?

>
>
> PS: Iteration is cheating. Sorry Issac.
>
>
> <snip>
> the responses would be far more interesting than merely "looking up" the
> answer
> </snip>
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
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>
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> Elecraft web page: http://www.elecraft.com

AD5MA

Re: OT: math question

In reply to this post by Dan Barker

I always like to ask... "Is this a trick question?"

The way the problem is worded (and if I understand your geometry correctly)
implies an infinite number of solutions as long as the 20 foot ladder can
span the alley. Therefore, the width is anything less than or equal to 20
feet.

Al.

----- Original Message -----
From: "Dan Barker" <[hidden email]>
To: <[hidden email]>; "Elecraft" <[hidden email]>
Sent: Wednesday, March 30, 2005 2:22 PM
Subject: RE: [Elecraft] OT: math question

> I ran into a brain-teaser once, that had me baffled for hours (I won't say
> how many). Finally, I called my sister, the Rocket Scientist ("actually,
> we're not _Rocket_ scientists" - That's a quote from her husband) and
asked
> her.
>
> She and Paul spent a few minutes on the problem, figured it out, but it
was
> such a trivial answer they threw it away. Since I'd spent so long on the
> Question, I gave her about a week and then I called back. Luckily they'd
not

nor
> bends, blah blah blah...
>
> This should make some juices flow out there. Just simple geometry, or is
it?

James C. Hall, MD-2

RE: OT: math question

In reply to this post by S55M

Hmmm ... never seen square root as O with dot-dot on top.

Jamie
WB4YDL

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of S55M
Sent: Wednesday, March 30, 2005 2:47 PM
To: Elecraft
Subject: Re: [Elecraft] OT: math question

Yes math is beautifull (callculating needed space for 3d antennas HI.
But google can spare some time and paper.

:)
http://home.att.net/~numericana/answer/algebra.htm#quartic

----- Original Message -----
From: "Dan Barker" <[hidden email]>
To: <[hidden email]>; "Elecraft" <[hidden email]>
Sent: Wednesday, March 30, 2005 10:22 PM
Subject: RE: [Elecraft] OT: math question

> I ran into a brain-teaser once, that had me baffled for hours (I won't say
> how many). Finally, I called my sister, the Rocket Scientist ("actually,
> we're not _Rocket_ scientists" - That's a quote from her husband) and
asked
> her.
>
> She and Paul spent a few minutes on the problem, figured it out, but it
was
> such a trivial answer they threw it away. Since I'd spent so long on the
> Question, I gave her about a week and then I called back. Luckily they'd
not

nor
> bends, blah blah blah...
>
> This should make some juices flow out there. Just simple geometry, or is
it?

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Andrea Borgia

Re: OT: math question

James C. Hall, MD wrote:

> Hmmm ... never seen square root as O with dot-dot on top.

Right, they should have printed it as dah-dah-dah-dit ;-P
Sorry, couldn't resist this one 8-)

B73,
Andrea.

--
Homepage: http://andrea.borgia.bo.it / Amateur radio: IZ4FHT
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David A. Belsley

Re: OT: math question

In reply to this post by Dan Barker

I'll go with an alley of zero width.

best wishes,

dave belsley, w1euy

On Mar 30, 2005, at 3:22 PM, Dan Barker wrote:

> I ran into a brain-teaser once, that had me baffled for hours (I won't
> say
> how many). Finally, I called my sister, the Rocket Scientist
> ("actually,
> we're not _Rocket_ scientists" - That's a quote from her husband) and
> asked
> her.
>
> She and Paul spent a few minutes on the problem, figured it out, but
> it was
> such a trivial answer they threw it away. Since I'd spent so long on
> the
> Question, I gave her about a week and then I called back. Luckily
> they'd not
> taken out the trash, so she easily found their notes and read them to
> me.
>
> I won't spoil it for you 'crafters.
>
> Dan / WG4S / K2 #2456
>
> Problem: An alley has a 20-foot ladder across it, in the left lower
> corner
> and leaning on the right wall. There also is a 30-foot ladder, from the
> right lower corner leaning on the left wall. The laders cross at 10
> feet
> high.
>
> How wide is the alley?
>
> Usual conventions: alley is all right angles, ladders have no
> thickness nor
> bends, blah blah blah...
>
> This should make some juices flow out there. Just simple geometry, or
> is it?
>
>
> PS: Iteration is cheating. Sorry Issac.
>
>
> <snip>
> the responses would be far more interesting than merely "looking up"
> the
> answer
> </snip>
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>

Able2fly

Re: OT: math question

In reply to this post by Able2fly

That can't be right. Drawing it (roughly) on paper shows it to be around 13
feet wide, give or take a foot or so. But coming up with a precise equation
takes more math skills than high school left me with...

Bill K3UJ

========================================
In a message dated 3/30/2005 4:51:20 P.M. Eastern Standard Time,
[hidden email] writes:

I'll go with an alley of zero width.

best wishes,

dave belsley, w1euy

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Thom LaCosta

Re: OT: math question

In reply to this post by S55M

On Wed, 30 Mar 2005, S55M wrote:

> Yes math is beautifull (callculating needed space for 3d antennas HI.
> But google can spare some time and paper.
>
> :)
> http://home.att.net/~numericana/answer/algebra.htm#quartic

ANd now I know why my daughters always hated math, and why I never passed the
test to get recruited by various federal agencies.

I(we) are dumb.

73
Thom
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David A. Belsley

Re: OT: math question

In reply to this post by Able2fly

Well, Bill, my first answer of zero feet width is, in fact, a correct
answer, albeit rather degenerate. It was an answer that came
immediately to mind. However, there is a nondegenerate answer, which
is

approximately 12.3119 feet.

best wishes,

dave belsley, w1euy

> That can't be right. Drawing it (roughly) on paper shows it to be
> around 13 feet wide, give or take a foot or so. But coming up with
> a precise equation takes more math skills than high school left me
> with...
>
>
> Bill K3UJ
>
>
> ========================================
>
> In a message dated 3/30/2005 4:51:20 P.M. Eastern Standard Time,
> [hidden email] writes:
>
> I'll go with an alley of zero width.
>
> best wishes,
>
> dave belsley, w1euy_______________________________________________

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