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I note that C is described as being the maximum possible speed/velocity.
If speed is the rate of change of position, isn't then the maximum possible speed 2C?
Turn on a light bulb (in a vacuum). Instanteously a wave front (photons) are moving in direction x at a velocity of C relative to the bulb, or the original position.
Also instantaneously, another wave front (photons)are moving in the opposite direction at a velocity of C. Photons in the moving in the original direction are moving at a velocity of 2C RELATIVE to the photons moving in the second direction x - 180degrees.
- Guy Eltringham (age 66)
Los Angeles California USA
We recently answered a similar question about that, although it had to do with space ships and not light beams. Type the number 15917 in the search box. Give it a look and if you still have questions let us know.
(published on 08/20/10)
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