Tutorial: Relativity - what is a reference frame?

Discussion in 'Physics & Math' started by James R, Aug 19, 2012.

  1. Tach Banned Banned

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    This is getting worse and worse.


    But you tried attaching it to the light sphere. Which is totally fringe.
     
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  3. geistkiesel Valued Senior Member

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    James R:We could achieve the same velocity for the ball in a different way, of course. We could hold the stick and clocks "stationary" and move the ball along the sticks, instead of holding the ball stationary and moving the reference frame. In either case, the speed of the ball would be the same in the reference frame.

    Geist: One cannot argue with definitions but when moving the sticks and clock passed the ball the ball does not have a component of momentum greater than zero in either the clock/stick frame or the ball frame. If the ball is gently placed on the stick/clock frame the ball will acquire momentum, but the momentum sitting beside the sticks and clock is zero.

    JAmes R: More points to appreciate: EVERY reference frame - every set of sticks and clocks - is attached somewhere. The position of any given object may be different in different reference frame, as may its velocity and acceleration. Also, it makes no sense to define "position", "velocity" or "acceleration" in the absence of a reference frame.

    If a light pulse is emitted from an inertial transponder in the direction of another transponder and is reflected back to the origin and if the time-of –flight of the out-going pulse and incoming pulse were able to be measured and were found to differ, say the outgoing trajectory were greater than the incoming trajectory then the difference in lengths would be a measure of transponder distance traveled during the time of round trip flight of the pulses.
    I appreciate the clear frame definitions in your thread.
    Yrs, Geistkiesel (AKA Mike)
     
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  5. James R Just this guy, you know? Staff Member

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    geistkiesel:

    I replied to your post yesterday, before the forum was rolled back. Sorry, but I can't face going through it all again.
     
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  7. geistkiesel Valued Senior Member

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    Sorry, where is the post of your reply?
    G
     
  8. James R Just this guy, you know? Staff Member

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    ]

    It got lost. We lost 24 hours worth of posts due to a database error.
     
  9. geistkiesel Valued Senior Member

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    James R
    what was approximate length of your reply?
    g
     
  10. geistkiesel Valued Senior Member

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    Neddy Bate

    If we place some light detectors along the way both observers having access to the readouts both observers will measure the same initial detection time. So an actual 'moving' observer would determine that all subsequent periodic pulses would not reach the detectors at the same time and the moving observer would conclude that the detector was moving or that the lantern was moving. If the actual moving observer saw the other observer apparently moving away, as he considered himself stationary, then when viewing the light detector readings the time difference between each subsequent the 'moving observer's' reading would continually decrease, thus the moving observer must conclude that he is indeed moving.
    Geistkiesel (AKA Mike)
     

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