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Re: Walking the dog.

From Sergio <invalid@invalid.com>
Newsgroups sci.physics
Subject Re: Walking the dog.
Date 2016-07-20 08:05 -0500
Organization Aioe.org NNTP Server
Message-ID <nmnsv9$t81$1@gioia.aioe.org> (permalink)
References (1 earlier) <q9i06d-0ni.ln1@mail.specsol.com> <nmkbqv$1c9$1@gioia.aioe.org> <mhp06d-pdj.ln1@mail.specsol.com> <73fda72a-3727-425d-ab54-21972ab3dc92@googlegroups.com> <nmm0a2$hkh$1@gioia.aioe.org>

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On 7/19/2016 2:50 PM, Sergio wrote:
> On 7/19/2016 2:05 PM, Double-A wrote:
>> On Monday, July 18, 2016 at 10:31:06 PM UTC-7,
>> ji...@specsol.spam.sux.com wrote:
>>> Sergio <invalid@invalid.com> wrote:
>>>> On 7/18/2016 10:10 PM, jimp@specsol.spam.sux.com wrote:

>>>>>> Walking the dog.
>>>>>> Jane is walking her dog, spot. She sees her friend, Dick, walking
>>>>>> toward
>>>>>> her along the same long, straight road. Both Dick and Jane are
>>>>>> walking
>>>>>> at 3 mph. When Dick and Jane are 600 feet apart, Spot runs from
>>>>>> Dick to
>>>>>> Jane, turns and runs back to Dick, and then back and forth between
>>>>>> them
>>>>>> at constant speed of 8 mph. Dick and Jane both continue walking
>>>>>> toward
>>>>>> each other at a constant 3 mph. Neglecting the time lost each time
>>>>>> Spot
>>>>>> reverses direction, how far has Spot run in the time it takes Dick
>>>>>> and
>>>>>> Jane to meet?
>>>>>
>>>>> If spot can only run 8 mph, it is either sick or a tiny little rat
>>>>> dog.
>>>>>


time till Dick and Jane bump = 600ft at a closing velocity of 6 mph


6 mph = 8.8 ft/sec

600ft/ (8.8ft/sec) = 68.1818 seconds until Dick and Jane hit each other.

dog runs at 8 mph = 11.733 feet per second

distance Spot runs is 11.733 ft/sec * 68.1818 seconds = 799.977 feet.


Extra Credit:
list all the assumptions used to convert from real world to thought 
experiment;

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Thread

Walking the dog. Sergio <invalid@invalid.com> - 2016-07-18 20:28 -0500
  Re: Walking the dog. noTthaTguY <abu.kuanysh05@gmail.com> - 2016-07-18 18:40 -0700
    Re: Walking the dog. Sergio <invalid@invalid.com> - 2016-07-18 21:09 -0500
  Re: Walking the dog. jimp@specsol.spam.sux.com - 2016-07-19 03:10 +0000
    Re: Walking the dog. Sergio <invalid@invalid.com> - 2016-07-18 23:54 -0500
      Re: Walking the dog. jimp@specsol.spam.sux.com - 2016-07-19 05:13 +0000
        Re: Walking the dog. Double-A <double-a3@hush.com> - 2016-07-19 12:05 -0700
          Re: Walking the dog. Sergio <invalid@invalid.com> - 2016-07-19 14:50 -0500
            Re: Walking the dog. Sergio <invalid@invalid.com> - 2016-07-20 08:05 -0500
              Re: Walking the dog. Sergio <invalid@invalid.com> - 2016-07-20 08:32 -0500
            Re: Walking the dog. Double-A <double-a3@hush.com> - 2016-07-22 14:03 -0700
              Re: Walking the dog. "hanson" <hanson@quick.net> - 2016-07-22 14:52 -0700
                Re: Walking the dog. Double-A <double-a3@hush.com> - 2016-07-22 15:06 -0700
                Re: Walking the dog. "hanson" <hanson@quick.net> - 2016-07-23 18:44 -0700
                Re: Walking the dog. "hanson" <hanson@quick.net> - 2016-07-23 18:38 -0700
                Re: Walking the dog. "hanson" <hanson@quick.net> - 2016-07-23 15:53 -0700
  Re: Walking the dog. Michael J. Strickland <michael06582@comcast.net> - 2016-07-21 02:13 -0400
  Walking the dog. HVAC <mr.hvac@gmail.com> - 2016-07-22 03:56 -0700
    Re: Walking the dog. Sergio <invalid@invalid.com> - 2016-07-22 10:34 -0500
    Re: Walking the dog. benj <benj@nobody.net> - 2016-07-22 16:51 -0400

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