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Fast moving bird

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W. H.

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May 23, 2003, 1:54:07 PM5/23/03
to
A man is showing a friend his new radar gun that is used for measuring
speed, he spots a goose coming towards them and asks his friend to see
how fast it is flying. The friend is surprised that the reading is 165
miles per hour, and suggests that there is a problem with the
instrument, but owner of it tells him that it's working just fine. How
is this so?

Will

Mark Brader

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May 23, 2003, 2:44:31 PM5/23/03
to

Possible spoilers and supplementary problem:

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First, the radar gun displays the speed of the fastest object moving
toward it -- not the whole goose but its wingtips as they return
forward between one stroke and the next, presuming the gun is sensitive
enough to detect them. But I don't imagine that they return at anywhere
near 165 mph; the forward stroke would then take something like 1/100
of a second.

Second, the men could be riding on a moving vehicle.

Third, the gun might have detected an airplane behind the goose.

If you're riding on a train going north, parts of the train are going
south. Explain.
--
Mark Brader | "...it doesn't even fulfill the most basic
Toronto | requirements for a good text editor, such as
m...@vex.net | having a built-in mail reader." -- Per Abrahamsen

My text in this article is in the public domain.

Victor Schnapt_

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May 23, 2003, 2:53:25 PM5/23/03
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"W. H." <WHar...@webtv.net> wrote in message
news:14601-3EC...@storefull-2316.public.lawson.webtv.net...

Some potential SPOILERS

A few possibilities.

1) The men themselves are moving, thus changing the relative speed of closure.

2) The goose is power-diving or in free-fall (maybe after being shot). The
dives of peregrine falcons can exceed 200 mph, so I imagine any bird could dive
relatively rapidly.

3) The goose has been shot from a launcher. That sort of thing does happen, you
know, to test jet engines. The puzzle doesn't say the goose is flying, merely
"coming."

4) The goose is riding some sort of really fast vehicle.

I'd say that's enough for now.


W. H.

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May 23, 2003, 7:16:18 PM5/23/03
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>men could be riding on a moving vehicle.

Yes, the answer that I was looking for was that the men were in an
airplane.

Here's another one:

A police car is hot on the trail of a bank robber who has a good head
start, the officer is speeding through town at over 90 miles per hour,
and a dispatcher radios to him the location of the perp. With his
siren shrieking, he is flying around curves and finally he has the
suspect's car in sight, and while going 85 miles per hour, he hits it.
Later when they look at the cars to check out the damage, they find that
there is none. How could this be?

Will

Victor Schnapt

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May 23, 2003, 9:37:08 PM5/23/03
to
SPOILERS below.

"W. H." <WHar...@webtv.net> wrote in message

news:28691-3EC...@storefull-2315.public.lawson.webtv.net...

'Cause the suspect's car was going about 84.5 mph at the time.


Don Del Grande

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May 23, 2003, 9:34:25 PM5/23/03
to
WHar...@webtv.net (W. H.) wrote:

>A police car is hot on the trail of a bank robber who has a good head
>start, the officer is speeding through town at over 90 miles per hour,
>and a dispatcher radios to him the location of the perp. With his
>siren shrieking, he is flying around curves and finally he has the
>suspect's car in sight, and while going 85 miles per hour, he hits it.
>Later when they look at the cars to check out the damage, they find that
>there is none. How could this be?

SPOILER SPACE
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The suspect's car was going in the same direction, about 84 miles an
hour.

------------------------------------------------
Don Del Grande, del_g...@netvista.net
Or perhaps he "hit it" with his hand while wearing a boxing glove
(otherwise there could be damage to the hand)?

Bill Smythe

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May 23, 2003, 9:52:49 PM5/23/03
to
"W. H." wrote:
> .... while going 85 miles per hour, he hits it.

> Later when they look at the cars to check out the damage, they find that
> there is none. How could this be? ....

Easy --

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The suspect's car was going 84 mph, and both cars were able to withstand a
1-mph collision.

Bill Smythe

Ted S.

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May 23, 2003, 11:20:23 PM5/23/03
to
Somebody claiming to be m...@vex.net (Mark Brader) wrote in
news:j_tza.208$6k3.20...@news.nnrp.ca:

>Will H. writes:
>>A man is showing a friend his new radar gun that is used for measuring
>>speed, he spots a goose coming towards them and asks his friend to see
>>how fast it is flying. The friend is surprised that the reading is 165
>>miles per hour, and suggests that there is a problem with the
>>instrument, but owner of it tells him that it's working just fine. How
>>is this so?
>
>Possible spoilers and supplementary problem:

Original post saved as spoiler space for the supplementary problem

The pattern of the wheels' rotation (when mapped onto graph paper) crosses
over itself? (I know there's some math jargon for this type of pattern,
but I can't remember it this late on a Friday evening.)

Either that, or that rod that goes between wheels on the same side of the
train goes at such a speed so as to be going south at times?
--
Ted Schuerzinger
Homer Simpson: I'm sorry Marge, but sometimes I think we're the worst
family in town.
Marge: Maybe we should move to a larger community.
<http://www.snpp.com/episodes/7G04.html>

Ed Murphy

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May 23, 2003, 11:25:53 PM5/23/03
to
On Fri, 23 May 2003 18:44:31 +0000, Mark Brader wrote:

> If you're riding on a train going north, parts of the train are going
> south. Explain.

[spoiler space]

As shown below, part of the wheel flange extends below the point where
the wheel touches the track. At any given moment, the lowest point of
the wheel is moving backward.

_____
/ \
/ \
| |
| * |
| |
_____\ /_____
\_____/

Alen Kalati

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May 24, 2003, 1:24:20 AM5/24/03
to
On Fri, 23 May 2003 13:54:07 -0400 (EDT), WHar...@webtv.net (W. H.)
wrote:

Is that an African goose, or a European one? Cause their wing flap
rates different you know... (Monty Paython and the holly
Graillllllllllllllllll)

AK

Alen Kalati

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May 24, 2003, 1:24:56 AM5/24/03
to
On Fri, 23 May 2003 19:16:18 -0400 (EDT), WHar...@webtv.net (W. H.)
wrote:

>>men could be riding on a moving vehicle.


- The police car is catapulted in the air (Like in the movies) and
while landing, it hits the radio antena on top of the roof of the
robber's car. The antena is flexible - no damage done.

- Both cars are rapped with 2 tons of cotton balls.


Martin Round

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May 24, 2003, 5:21:42 AM5/24/03
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"W. H." <WHar...@webtv.net> wrote in message
news:14601-3EC...@storefull-2316.public.lawson.webtv.net...

Nobody has said yet that the goose could be flying at a typical goose speed
(maybe 45mph) with a 120mph tail wind.

It would be a pretty stupid goose though to fly in a hurricane.

Martin.


Julie Waters

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May 24, 2003, 8:24:40 AM5/24/03
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In article <28691-3EC...@storefull-2315.public.lawson.webtv.net>,

WHar...@webtv.net (W. H.) wrote:
> A police car is hot on the trail of a bank robber who has a good head
> start, the officer is speeding through town at over 90 miles per hour,
> and a dispatcher radios to him the location of the perp. With his
> siren shrieking, he is flying around curves and finally he has the
> suspect's car in sight, and while going 85 miles per hour, he hits it.
> Later when they look at the cars to check out the damage, they find that
> there is none. How could this be?

Spoiler...


The other car is also going 85 mph at the moment of impact.

--julie
--
fire...@songweaver.com http://songweaver.com/puzzler/

The United States is seeking to avert further criticism
over the use of cluster bombs in Afghanistan by warning
the Afghan people not to confuse unexploded bombs with
food drops. --From a BBC broadcast, 10/28/01

Phil Carmody

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May 24, 2003, 11:24:06 AM5/24/03
to
On Sat, 24 May 2003 03:20:23 +0000, Ted S. wrote:
> The pattern of the wheels' rotation (when mapped onto graph paper) crosses
> over itself? (I know there's some math jargon for this type of pattern,
> but I can't remember it this late on a Friday evening.)

For points extending below the track level, yes. It's a prolate cycloid.

Phil

Mark Brader

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May 24, 2003, 2:16:00 PM5/24/03
to
Ted Schuerzinger:

> > The pattern of the wheels' rotation (when mapped onto graph paper) crosses
> > over itself? ...

Phil Carmody:


> For points extending below the track level, yes. It's a prolate cycloid.

Yes, and that's the key point: the wheel flanges extend below rail level.
--
Mark Brader | "...being permitted to propel a ton of steel through
Toronto | public places at speeds of up to 33 m/s is not a
m...@vex.net | fundamental human right in my book" -- Paul Ciszek

Bill Smythe

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May 25, 2003, 3:35:51 PM5/25/03
to
"Mark Brader" wrote:
> If you're riding on a train going north, parts of the train are going
> south. Explain.

This is a chestnut.

The center of the wheel is moving at the same speed as the train. The point
on the wheel which is (momentarily) at the top of the wheel is moving
(momentarily) at twice the speed of the train. The point on the wheel which
is (momentarily) at the bottom of the wheel (in contact with the track) is
moving (momentarily) at 0 mph. The flange, which extends beyond the edge of
the wheel, is moving backwards, at points which are (momentarily) near the
bottom of the wheel.

Bill Smythe

Ashish

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May 26, 2003, 5:55:19 PM5/26/03
to
>
> If you're riding on a train going north, parts of the train are going
> south. Explain.
> --

The train is taking a U turn?


--
-Ashish
--------------------------------------------------------------------------
Hi! I'm a shareware signature! Send $5 if you use me, send $10 for manual!
http://www.123ashish.com


raj

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May 26, 2003, 6:16:44 PM5/26/03
to

"Mark Brader" <m...@vex.net> wrote in message
news:j_tza.208$6k3.20...@news.nnrp.ca...
<snip>

> If you're riding on a train going north, parts of the train are going
> south. Explain.

Spoiler

*
*

You are in the lead car of a train that just passed through the south pole.

Bob


George Weinberg

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May 27, 2003, 11:14:40 AM5/27/03
to
On Mon, 26 May 2003 17:55:19 -0400, "Ashish" <ash...@hotmail.com>
wrote:

People are getting it on in the sleeper cars. "Going south" is
metaphorical.

George

Ashish

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May 27, 2003, 9:51:16 PM5/27/03
to

"George Weinberg" <eor...@covad.net> wrote in message
news:3ed38034....@news.covad.net...

You mean like my grades?
:-)

Eric Nielsen

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May 28, 2003, 9:05:13 AM5/28/03
to

Easy...the readout was being read upside-down. The goose was flying 591
mph.


George Weinberg

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May 28, 2003, 11:22:27 AM5/28/03
to
On Tue, 27 May 2003 21:51:16 -0400, "Ashish" <ash...@hotmail.com>
wrote:

>
>"George Weinberg" <eor...@covad.net> wrote in message
>news:3ed38034....@news.covad.net...
>> On Mon, 26 May 2003 17:55:19 -0400, "Ashish" <ash...@hotmail.com>
>> wrote:
>>
>> >>
>> >> If you're riding on a train going north, parts of the train are going
>> >> south. Explain.
>> >> --
>> >
>> >The train is taking a U turn?
>> >
>> >
>> >--
>> >-Ashish
>>
>>--------------------------------------------------------------------------
>> >Hi! I'm a shareware signature! Send $5 if you use me, send $10 for
>manual!
>> >http://www.123ashish.com
>> >
>> >
>> People are getting it on in the sleeper cars. "Going south" is
>> metaphorical.
>>
>
>You mean like my grades?
>:-)
>

Maybe... if you're working hard to earn extra credit!

Another answer: the molecules in the train are moving
pretty much in random directions at speeds much higher than the
CM motion of the train, so at any given instant nearly half the
molecules have motion that has a southward component,
and a couple are heading almost due south.

George

Eric Nielsen

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May 28, 2003, 8:55:47 PM5/28/03
to
> Maybe... if you're working hard to earn extra credit!
>
> Another answer: the molecules in the train are moving
> pretty much in random directions at speeds much higher than the
> CM motion of the train, so at any given instant nearly half the
> molecules have motion that has a southward component,
> and a couple are heading almost due south.

Unfortunately, "south" is referencing the Earth, which contains molecules
doing the same thing. Any meaningful declaration of relative motion can
only be done on a macroscopic scale in this case. Good try though :-)


Greg Neill

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May 27, 2003, 10:45:29 AM5/27/03
to
"Mark Brader" <m...@vex.net> wrote in message
news:j_tza.208$6k3.20...@news.nnrp.ca...

>


> If you're riding on a train going north, parts of the train are going
> south. Explain.

Train wheels have lips on their circumference that
extend a small amount past the track/wheel interface
on the outside edge. Since the point of contact
of the wheel and track is stationary in the track's
frame of reference, the part of the wheel's lip that
extends below the track/wheel interface must be
moving in the opposite direction to that of the
train.


Victor Schnapt_

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May 29, 2003, 1:48:16 PM5/29/03
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"Greg Neill" <gnei...@OVE.netcom.ca> wrote in message
news:ORKAa.55037$Em1.3...@wagner.videotron.net...

ObPuzzle: why do some people periodically respond to long-answered, long-dead
topics as though they had just seen them?

My best guess is "because they just saw them," but why are they just seeing
them?


Greg Neill

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May 29, 2003, 2:10:22 PM5/29/03
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"Victor Schnapt_" <sch...@yahoo.com> wrote in message
news:bb5ha2$5qnb9$1...@ID-175339.news.dfncis.de...

Possibly due to a severe shortage of omniscience.

A better question might be, "why do some people periodically
post long(since)-answered, long-dead topics as though the
world were new?"


Victor Schnapt_

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May 29, 2003, 2:15:33 PM5/29/03
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"Greg Neill" <gnei...@OVE.netcom.ca> wrote in message
news:h2sBa.3101$xG4....@weber.videotron.net...

> "Victor Schnapt_" <sch...@yahoo.com> wrote in message
> news:bb5ha2$5qnb9$1...@ID-175339.news.dfncis.de...
> > ObPuzzle: why do some people periodically respond to long-answered,
> long-dead
> > topics as though they had just seen them?
> >
> > My best guess is "because they just saw them," but why are they just
> seeing
> > them?
>
> Possibly due to a severe shortage of omniscience.
>
> A better question might be, "why do some people periodically
> post long(since)-answered, long-dead topics as though the
> world were new?"

Possibly due to a severe shortage of FAQ-reading and/or omniscience.

Though you're free to interpret as you wish, my post was not an insult to you.
I simply wonder why you're just now seeing a week-old topic. I've seen them
resurrected from several months in the past. Why is that?


Greg Neill

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May 29, 2003, 2:34:28 PM5/29/03
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"Victor Schnapt_" <sch...@yahoo.com> wrote in message
news:bb5imh$5vu69$1...@ID-175339.news.dfncis.de...

A combination of things, but primarily a less than
wonderful news server; posts from several weeks past
that never showed up on time will suddenly appear,
usually in a bunch. Unless I pay close attention to
the posting dates on every post I scan, I run the
risk of following up on old news.


John Bailey

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May 29, 2003, 2:45:35 PM5/29/03
to
On Fri, 23 May 2003 13:54:07 -0400 (EDT), WHar...@webtv.net (W. H.)
wrote:

>A man is showing a friend his new radar gun that is used for measuring


>speed, he spots a goose coming towards them and asks his friend to see
>how fast it is flying. The friend is surprised that the reading is 165
>miles per hour, and suggests that there is a problem with the
>instrument, but owner of it tells him that it's working just fine. How
>is this so?

At this late date and with so many other answers, do we need spoiler
space?

Oh, I guess so.

Spoiler Space


The man and his friend were trying out his new superlight sports
plane. Their greatest fun is playing goose with flying chickens. In
this case, they ran head on into a goose going about 55 mph, minding
his own business.

The landing speed of their superlight is about 30 mph, but it cruises
at 110 mph.

I hope this doesn't duplicate another answer. One came close, but
seemed to miss.

John Bailey
http://home.rochester.rr.com/jbxroads/mailto.html

Eric Nielsen

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May 30, 2003, 4:55:00 PM5/30/03
to
> Though you're free to interpret as you wish, my post was not an insult to
you.
> I simply wonder why you're just now seeing a week-old topic. I've seen
them
> resurrected from several months in the past. Why is that?

I set my reader to display the past two weeks of r.p posts because I don't
pass every waking hour reading usenet.


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