Re: Viewing the spokes

From	jimp@specsol.spam.sux.com
Newsgroups	sci.physics
Subject	Re: Viewing the spokes
Date	2016-09-10 01:33 +0000
Organization	A noiseless patient Spider
Message-ID	<uf4cad-fc2.ln1@mail.specsol.com> (permalink)
References	(2 earlier) <57d32ee0$0$43803$c3e8da3$5e5e430d@news.astraweb.com> <rkvbad-vs1.ln1@mail.specsol.com> <57d35734$0$31237$c3e8da3$dd9697d2@news.astraweb.com> <mc2cad-772.ln1@mail.specsol.com> <57d35ced$0$62038$b1db1813$2411a48f@news.astraweb.com>

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benj <benj@nobody.net> wrote:
> On 9/9/2016 8:57 PM, jimp@specsol.spam.sux.com wrote:
>> benj <benj@nobody.net> wrote:
>>> On 9/9/2016 8:10 PM, jimp@specsol.spam.sux.com wrote:
>>>> benj <benj@nobody.net> wrote:
>>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, Sergio wrote:
>>>>>>> Viewing the spokes
>>>>>>>
>>>>>>> A wheel with spokes rolls on the ground. A stationary camera takes a
>>>>>>> picture of the wheel. Due to the nonzero exposure time of the camera,
>>>>>>> the spokes will generally appear blurred. At what location(s) in the
>>>>>>> picture does (do) the spoke(s) not appear
>>>>>>> blurred?
>>>>>>
>>>>>>>
>>>>>>> answer,
>>>>>>>
>>>>>>>
>>>>>>> The contact point on the ground does not look blurred, because it is
>>>>>>> instantaneously at rest.
>>>>>>
>>>>>>   There is no "instantaneous". The wheel *moves* while the shutter is open, hence the contact patch will move, hence the lowermost spokes will be blurred.
>>>>>>
>>>>>>   Now, if you want to talk about which spokes will be *least* blurred...
>>>>>>
>>>>>>
>>>>>>   Mark L. Fergerson
>>>>>>
>>>>> Actually, Mark, only the point of the wheel touching the ground which
>>>>> would be the rim is at rest. And even then that "point' will be
>>>>> rotating. But as we all know from the establishment science everyone
>>>>> here believes in, the rotation of a point particle will not produce any
>>>>> blurring in the camera image. OF course that "point particle" is NOT
>>>>> located on a spoke so for that reason your answer stands as correct.
>>>>
>>>> A point is a mathematical construct and has nothing to do with cameras
>>>> in the real world.
>>>>
>>>> During the time the shutter is open, EVERYTHING on the wheel is moving
>>>> some amount both in rotation and linearly.
>>>>
>>>> How blurred anything is depends on the rotational and linear speed of
>>>> the wheel relative to the view of the camera, the exposure time and the
>>>> resolution of the camera.
>>>
>>> We are all well aware of this jim. However the point touching the ground
>>> does not move linearly as I've already noted. Hence you should have said
>>> "rotation OR linearly" rather than "rotation and linearly".
>>
>> Set the camera exposure time to 1 hour.
>>
>> How far does the point touching the ground move in 1 hour?
> 
> Doesn't move at all because if the same point is touching the ground for 
> an hour then the wheel isn't turning very fast. In fact I say the wheel 
> is turning extremely slowly. There goes your logic out the window.

I did not say the same point was touching the ground for an hour.

What I did say was that the problem depends on the rotational and linear
speed of the wheel relative to the view of the camera.

> (We all observe that the angular velocity of the wheel has not been 
> specified, right? Right.)

OK, the angular velocity of the wheel is such that it's linear velocity
over the ground is equal to the field of view of the camera in 1 hour
and the shutter is opened when the bottom of the wheel is at the edge
of the field of view.

Exposure time is still 1 hour.

The point touching the ground appears as a steak that is the sum of the
exposure of the point touching the ground AND the background, whatever
it is.


-- 
Jim Pennino

Thread

Viewing the spokes Sergio <invalid@invalid.com> - 2016-08-29 12:08 -0500
  Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-08-29 18:00 +0000
    Re: Viewing the spokes benj <benj@nobody.net> - 2016-08-29 21:00 -0400
      Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-08-30 01:14 +0000
        Re: Viewing the spokes benj <benj@nobody.net> - 2016-08-29 22:45 -0400
          Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-08-30 04:14 +0000
            Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-29 21:59 -0700
              Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-08-30 05:16 +0000
                Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-29 23:00 -0700
    Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-08-29 18:29 -0700
  Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-29 18:29 -0700
  Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-29 18:46 -0700
    Re: Viewing the spokes benj <benj@nobody.net> - 2016-08-30 19:40 -0400
      Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-30 22:07 -0700
        Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-30 23:48 -0700
          Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-31 09:54 -0700
            Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-09-02 10:00 -0700
              Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-02 13:23 -0700
              Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 11:30 -0700
                Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 13:18 -0700
                Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 14:57 -0700
                Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 16:01 -0700
                Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-04 12:46 -0700
                Re: Red, Blue and Green Ergios <invalid@invalid.com> - 2016-09-07 12:32 -0500
                Re: Red, Blue and Green noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-08 12:12 -0700
                Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-07 23:22 -0700
                Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 16:03 -0700
                Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 16:06 -0700
                Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-20 00:18 -0700
                Re: Red, Blue and Green noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-20 12:52 -0700
                Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-07 10:01 -0700
                Re: Red, Blue and Green Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-07 10:12 -0700
                Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-20 09:47 -0700
        Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-08-31 14:32 -0700
  Re: Viewing the spokes "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-09-04 11:39 -0700
    Re: Viewing the spokes "hanson" <hanson@quick.net> - 2016-09-04 20:36 -0700
  Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-09 09:08 -0700
    Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-09 12:32 -0700
    Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-09 17:51 -0400
      Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-10 00:10 +0000
        Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-09 20:43 -0400
          Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-10 00:57 +0000
            Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-09 21:07 -0400
              Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-10 01:33 +0000
                Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-12 20:59 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-13 02:41 +0000
      Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-09 19:43 -0700
        Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-12 21:29 -0400
          Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-13 02:43 +0000
          Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-13 13:28 -0700
          Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-13 17:14 -0700
            Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-13 21:52 -0400
              Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-14 05:11 +0000
                Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-15 17:49 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-16 00:50 +0000
                Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-15 21:52 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-16 04:11 +0000
                Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-16 16:58 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-16 21:40 +0000
                Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-16 20:56 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-17 01:47 +0000
                Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-17 17:24 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-18 00:07 +0000
              Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-14 14:26 -0700
                Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-14 15:04 -0700
                Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-16 12:54 -0700
              Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-14 19:47 -0700
                Re: Viewing the spokes benj <nobody@gmail.com> - 2016-09-14 23:24 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-15 05:12 +0000
                Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-15 15:45 -0700
                Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-15 21:36 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-16 02:58 +0000
                Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-18 12:15 -0700
    Re: Viewing the spokes Wally W. <ww84wa@aim.com> - 2016-09-15 09:15 -0400
      Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-15 15:48 -0700
        Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-18 15:33 -0700

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