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Special Relativity (1 Viewer)
- Thread starter Petyo
- Start date
Pwnage101
Moderator
i went through that very same phase a year ago (i even lost sleep over it!)Petyo said:
With (HSC level) Physics there isn't much prooving involved. Basically, you have to just have to accept the concept and apply it.
I didn't lose much sleep over this TBH. It's dead easy once you get your head around it.
I didn't lose much sleep over this TBH. It's dead easy once you get your head around it.
Hey Petyo,
THis is how i see it.
Right so Einsteins Gedankan. Einstein hypothesised about a train travelling at the speed of light and an observor watching it from a platform. Now a mirror is placed in the train and einstein asks will a man standing in the train See himself in the mirror?
IF NO: It means that he KNOWS he is travelling at the speed of light
(thats why light cant catch up, this is a bit tricky. Imagine you and a friend running along a road both at the Speed X. Imagine you start 5 seconds before your friend, isnt it true to say your friend will never catch you?) Similarly if he doesnt see his reflection it goes to say that light does not catch up to the train (which is travelling at the speed of light). But this means HE MUST KNOW that he is travelling at the speed of light (because that would be the only way he wouldnt be able to see his reflection). However according to Gallielo's theory of relatvity, in an intertial frame of reference (in this case the train) you cannot make any measurements of speed without reference to an external point (implying that time, distance, mass, etc are INVARIABLE), hence if he was to see his reflection he would know he was travelling a tthe speed of light and theory of relativity would be violated.
PHEW! Hope you understood that!
NOW...
IF YES: SO lets assume he does see his reflection. That would mean that some random bloke standing on a platform outside will see light catching up to the train (remember the train is already travelling at the speed of light). Let us go back to my earlier analogy, say you and your friend are running at speed X and you have started 5 seconds earlier, now lets say some person is watching you. The only logical way for the person to see your friend catching up to you is to see him running at a speed greater than X, say 2X.
Similarly the observor would see light travelling faster than the train to catch up. BUT THIS ISNT POSSIBLE! NOTHING CAN TRAVEL FASTER THAN THE SPEED OF LIGHT! Hence dear einstein drew the conclusion that length, mass, time, etc is indeed variable and that the speed of light is constant for all observors.
Hence there are consequences ie -> The distance of a metre was made based on the asummption that length was constanst. Due to theory of special relativity the length of a metre had to be changed. Also it opened up the concept of the space-time continuum which suggests we exist in 4 dimensions not 3.
BEST OF LUCK! Byee!
THis is how i see it.
Right so Einsteins Gedankan. Einstein hypothesised about a train travelling at the speed of light and an observor watching it from a platform. Now a mirror is placed in the train and einstein asks will a man standing in the train See himself in the mirror?
IF NO: It means that he KNOWS he is travelling at the speed of light
(thats why light cant catch up, this is a bit tricky. Imagine you and a friend running along a road both at the Speed X. Imagine you start 5 seconds before your friend, isnt it true to say your friend will never catch you?) Similarly if he doesnt see his reflection it goes to say that light does not catch up to the train (which is travelling at the speed of light). But this means HE MUST KNOW that he is travelling at the speed of light (because that would be the only way he wouldnt be able to see his reflection). However according to Gallielo's theory of relatvity, in an intertial frame of reference (in this case the train) you cannot make any measurements of speed without reference to an external point (implying that time, distance, mass, etc are INVARIABLE), hence if he was to see his reflection he would know he was travelling a tthe speed of light and theory of relativity would be violated.
PHEW! Hope you understood that!
NOW...
IF YES: SO lets assume he does see his reflection. That would mean that some random bloke standing on a platform outside will see light catching up to the train (remember the train is already travelling at the speed of light). Let us go back to my earlier analogy, say you and your friend are running at speed X and you have started 5 seconds earlier, now lets say some person is watching you. The only logical way for the person to see your friend catching up to you is to see him running at a speed greater than X, say 2X.
Similarly the observor would see light travelling faster than the train to catch up. BUT THIS ISNT POSSIBLE! NOTHING CAN TRAVEL FASTER THAN THE SPEED OF LIGHT! Hence dear einstein drew the conclusion that length, mass, time, etc is indeed variable and that the speed of light is constant for all observors.
Hence there are consequences ie -> The distance of a metre was made based on the asummption that length was constanst. Due to theory of special relativity the length of a metre had to be changed. Also it opened up the concept of the space-time continuum which suggests we exist in 4 dimensions not 3.
BEST OF LUCK! Byee!
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