Re: Time dilation pre-Einstein


"harry" <harald.vanlintelButNotThis@xxxxxxx> wrote in message
news:1216901472_696@xxxxxxxxxxxxxxxxxxx
|
| "Uncle Ben" <ben@xxxxxxxxxxx> wrote in message
| news:c0a17537-e183-468a-99ad-0269bddcb67a@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
| > Electromagnetic theory says that a moving charge creates a magnetic
| > field that acts on any other moving charge with a force qv x B.
| >
| > So let us consider two charged ping-pong balls at rest in the
| > laboratory frame of reference. If this laboratory happens to be in
| > outer space, we can release them and watch them move apart because of
| > electrostatic repulsion.
| >
| > Another laboratory in another spaceship flies by. Relative to the
| > second laboratory, we have moving charges. One creates a magnetic
| > field with lines of force as circles around its path. Assume the
| > direction of motion is such that the two balls are on a line
| > perpendicular to the motion, so the second ball is moving right
| > alongside the first ball and can feel its magnetic field at maximum
| > strength.
| >
| > We see that v x B is in the direction such that the force is
| > attractive, making the two balls repel each other with less force than
| > the electrostatic force. If you work it all out quantitatively, the
| > magnetic force is always weaker than the electrostatic force, but with
| > faster motion, it increases, approaching the strength of the
| > electrostatic force as the speed approaches the speed of light as a
| > limit. See the Feynman Lectures on Physics for the full details.
| >
| > So if we release the balls and let them fly apart, we see that the
| > acceleration w.r.t. the second laboratory is slower. In the limit as
| > the speed approaches c, the acceleration stops, because the two forces
| > are equal and opposite.
| >
| > This is exactly what happens if time is dilated. The motion slows down
| > because time slows down w.r.t. the second spaceship laboratory. Time
| > doesn't slow down w.r.t. the first spaceship laboratory, and the balls
| > fly apart quickly. Time is relative!
| >
| > Isn't that amusing!
|
| The nice thing of physics is that it all fits together - or at least, it
| should be like that! :-)
|
| > It shouldn't be surprising however if you understand that magnetism is
| > just the relativistic manifestation of electrostatics w.r.t. a
| > different frame of reference. But nobody realized that before
| > Einstein.
|
| I'm afraid that that is a (popular) misconception. For example: you would
| impress me if you could correctly describe the magnetic field of a
magnetic
| coil (fed by a battery) as "just the relativistic manifestation of
| electrostatics w.r.t. a different frame of reference".
|
| Harald

You would impress me if you could take you head out of your arse.

Why did Einstein say
the speed of light from A to B is c-v,
the speed of light from B to A is c+v,
the "time" each way is the same?


"Easy: he did NOT say that." - cretin harald.vanlintelButNotThis@xxxxxxx
According to moron van lintel, Einstein did not write this equation.

http://www.fourmilab.ch/etexts/einstein/specrel/www/figures/img22.gif








.

Relevant Pages

  • Time dilation pre-Einstein
    ... So let us consider two charged ping-pong balls at rest in the ... laboratory frame of reference. ... It shouldn't be surprising however if you understand that magnetism is ... just the relativistic manifestation of electrostatics w.r.t. a ...
    (sci.physics.relativity)
  • Re: Time dilation pre-Einstein
    ... laboratory frame of reference. ... since the field is made up of contributions from the electrons. ... But I am satisfied by Feynman's argument that magnetism is basically a ...
    (sci.physics.relativity)
  • Re: Time dilation pre-Einstein
    ... laboratory frame of reference. ... since the field is made up of contributions from the electrons. ... But I am satisfied by Feynman's argument that magnetism is basically a ...
    (sci.physics.relativity)
  • Re: Balls Magnetized
    ... For the record any steel will magnetize, ... higher carbon will hold more of a charge. ... You want balls with less carbon if you are ... worried about magnetism. ...
    (rec.games.pinball)
  • Re: Question about magnetic forces beyond saturation
    ... We did not cover magnetism in depth in my Year 12 Physics syllabus, ... particularly what happens beyond saturation. ... Based on my understanding of gravity and electrostatics, ... while diamagnetic materials will have negative B-fields? ...
    (sci.physics.electromag)