Confusion on Special Relativity (1 Viewer)

Sonata

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im kinda lost with the length contraction, mass dilation, time dilation. i dun get the theory of how wen sumthing is travelling at the spd of light that the object gets affected in size, mass etc.. Exactly how does it work?
 

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Remember s = v t and E = m c2 in my explanation.

Special relativity goes on the assumption that the speed of light is the same in all inertial frames of reference irrespective of the motion of the observer (say a ship on the ocean) or source (say a light in the lighthouse).

v = s / t, so if the speed of light with speed v stays the same throughout then distance and time become relative.
So as something travels faster and faster it becomes shorter lengthwise (length contraction) but takes more time to do so (time dilation).

There is the law of energy conservation, but thanks to E = m c2 there is also the law of mass-energy conservation, they are both related.
(Example given upon request.)
As the object travels near the speed of light, the energy given to move an object making it go faster and faster at relativistic speeds is instead converted into mass (mass dilation).



Relativistic speeds are speeds near the speed of light say at least ~0.1c where c is 3 x 108 m s-1.
 

Sonata

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special relativity was a thought experient by einstein correct?
 

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Sonata said:
special relativity was a thought experient by einstein correct?
Special relativity is a theory developed by Einstein in response to the inconsistency of the aether model, it is not a thought experiment itself.

The thought experiment (gedanken) Einstein thought of involved the two trains passing each other with light sources placed at each end of the train, which involves the relativity of simultaneity.
 

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Special theory of relativity is a consequence of the null result brought on by Michelson/Morley half silvered mirror experiment.

Without this experiment Einstein may not have been as popular as he is today.

I'll give him credit for the photoelectric effect in which he won a nobel prize for.
 

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To answer the OP question,

Think of the Michelson/Morley experiment and understand the significance of the null result i.e. that there was no signifcant fringe shift measured (mathematically it was proven to have occured) and this troubled the Physics community and boffins.

So along comes Einstein and puts postulates down to address this null result.

The gist of it goes like this:

* The null result provides the fact that light travels at c in all directions regardless of the motion of the observer. This contradicts Newtonian relativity and hence the need for a new form of relativity. Funnily enough there were other scientisits and mathematicians at the time suggesting general theory of relativity but somehow? Einstein received the recognitions whilst the others smothered in the dust.. SOme say his theory was King...
* Einstein said and this is most important is that for c to exist in a uniform speed in all directions consequently something else must change to accomodate this fact. What changes????
* Time dilates in the inertial frame of reference i.e. the earth clock think twin paradox here...
* Mass increases
* length contracts

As another poster revealed if v is to remain contant in v=d/t if d decreases/contraction then t must dilate to equate v=c

Fire away any other questions you have and I will try to answer them for you.
My students have an excellent grasp of the historical viewpoints behind the leadup to the theory of relativity. It is something all students should look at to understand how the Scientists of that era came up with their theories.

Strangely enough Einstein was more influenced by Lorentz and I reckon he plagiarized some of his work. Einstein states in his biographies the null result was not a worry for him. WEIRD!!!!

Good luck..
 

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