Einstein's Constant: The Speed of Light Irrespective of Source

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Discussion Overview

The discussion revolves around the concept of the speed of light being constant regardless of the speed of its source, as proposed by Einstein. Participants explore this idea through hypothetical scenarios involving a supersonic car and the implications of special relativity on the addition of velocities.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant asserts that if they are in a supersonic car moving at 8 Mach and throw a ball forward, the ball's speed would be the sum of its speed and the car's speed.
  • Another participant challenges this claim, stating that the ball would not have that exact speed but would be slightly less due to relativistic effects.
  • A different participant expresses confusion about the implications of the speed of light, questioning whether light can exceed its own speed.
  • One participant emphasizes that Einstein's theory of special relativity is well-established and suggests that any perceived trivial errors in understanding are likely due to misunderstandings by the questioner.
  • A participant provides a mathematical formula for velocity addition in special relativity, indicating that the simple addition of speeds does not apply when velocities approach the speed of light.
  • Another participant expresses gratitude for the clarification, indicating some level of understanding has been achieved.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the application of classical versus relativistic physics to the scenario presented. While some participants accept the principles of special relativity, others remain confused about its implications.

Contextual Notes

The discussion includes assumptions about the applicability of Newtonian physics versus special relativity, and the limitations of understanding regarding the speed of light and velocity addition. There are unresolved questions about the nature of light speed and its implications in different frames of reference.

HIGHLYTOXIC
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Einstein said that the speed of light will be constant irrespective of the speed of its source..

So, suppose your are onboard a supersonic car (imagine!) with the speed of 8 Mach, and you throw a ball in the same direction with a speed of say 1500m/s, the ball will actually have the velocity of 1500 M/s + 8 Mach..

Now instead of the ball, take a torch & switch it on..Einstein says that Light wud still travel at c m/s and not c + 8 Mach m/s...

Can anyone justify this? Is there any proof of this??

Thanx!
 
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HIGHLYTOXIC said:
So, suppose your are onboard a supersonic car (imagine!) with the speed of 8 Mach, and you throw a ball in the same direction with a speed of say 1500m/s, the ball will actually have the velocity of 1500 M/s + 8 Mach..

No, the ball will not have that speed exactly. It will have a speed that is slightly less.

Can anyone justify this? Is there any proof of this??

Yes, there is plenty of experimental evidence that the lighspeed barrier cannot be broken. Have you looked into it yourself?
 
Yeah actually, I have read a lot on light speed barrier...Infinte mass & infinite force, rate of time being affected etc etc...But I just dun get this thing, CANT EVEN LIGHT OUTSPEED LIGHT?
 
HIGHLYTOXIC said:
Einstein said that the speed of light will be constant irrespective of the speed of its source..

So, suppose your are onboard a supersonic car (imagine!) with the speed of 8 Mach, and you throw a ball in the same direction with a speed of say 1500m/s, the ball will actually have the velocity of 1500 M/s + 8 Mach..

Now instead of the ball, take a torch & switch it on..Einstein says that Light wud still travel at c m/s and not c + 8 Mach m/s...

Can anyone justify this? Is there any proof of this??

Thanx!

Reemeber Einstein was hradly a dunce, he certainly would not of missed something as simple as this (and that also goes for the millions of people who have learned the theory of special relativity since it was conceived). There's a good rule of thumb for this situation, if you find a trivial error in a simple, well-known theory that has been around for a century it is almost certainly you who have made the error (thats's not aimed at you in particular more at certain other postes who will remain nameless *cough*geistkeisel*cough*).

In Newtonian physics the velocity is subject to a simply vecor addition, that is to say if you were standing on the ground and spersonic car wizzed past you with velocity u and threw the occupant of the car threw a ball with velocity v (relative to the car), you would measure the velocity of the ball w as:

w = u + v

N special relativity things are not so simple as the above formula becomes:

[tex]w = \frac{u + v}{1 - \frac{uv}{c^2}}[/tex]

Now you can see from the formula when u and v are much smaller than c,

w = u + v

is a very, very good approximation.
 
Hmm..I think I have got it now..Thanx for help!
 

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