It is a well discussed idea that moving mass and rest mass are different.
m= mo/[1-(v^2/c^2)]^(1/2).
Is it correct ?
Thsnks in advance.
Regards
Nityananda Das
Nityananda, yes, this is the effect of speed on the mass of a particle, as described in special relativity theory. And the same factor is also used to describe the dilation of time, inside the moving frame of reference, and the reduction in length of the traveling object.
Gamma = 1 / sqr(1 - v^2/c^2)
time inside moving frame of reference = time at rest * Gamma
mass = mass at rest * Gamma
length of object = length of object at rest / Gamma
That last one is interesting. You can actually do a mental exercise to figure out why it must be so. Think of a very long train, going faster and faster. As you sit still, watching the train go by, there will always be a time lag, from when the front of the train goes by you, and when the end of the train goes by you.
But at the speed of light, time inside that train will be "infinitely dilated," which means that the observer at rest will instantly disappear. At the speed of light, everything outside that train changes infinitely fast, from the perspective of someone inside. So there is no way the observer at rest can detect any time lag, from seeing the front of the train going by, to seeing the back of the train going by, even if the train is really, really long. At the speed of light, to the observer at rest, the train has no length at all!
Of course, the train can never quite achieve v = c, but as it approaches v = c, time dilation will start to be more obvious, and the length will therefore appear to be reduced.
Dear Nityanda,
the inertia p changes non linearly with the squared speed, p=mv*gamma according to experiments in accelerators.
It is not appropriate to say that m=m0gamma, where m0 is the rest mass, it is an arbitrary move to make mass increase with gamma.
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