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relativity question (1 Viewer)

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ND

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Originally posted by Constip8edSkunk
but isnt length contraction and time dilation 2 sides of the same coin anyway?
Yeh but i'm arguing that they travel further because time travels slower, and so the distance is also shorter, not the other way around - cause and effect.
 

Rahul

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the time for the muons dilates, so their life spans increase...this is by observers on earth.

for the 'muons', they will be travelling at 0.999c, so the distance from the atmosphere to the earth's surface will contract, as that space will be travelling past them, relative to them being stationary. they will be travelingl at 0.999c and will cover a shorter distance, for them they will have lasted their 'normal' lifespan. but for an observer, the muons would have covered a long distance, hence they would have laster longer.
 
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Dangar

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aah i get it now. So the time dilation is the cause for an observer, whilst length contraction is the cause for the space ship (moving frame of reference). And the effect for both is that the ship goes a lot further in a shorter time thereby consuming less fuel. Thanks guys
 

CHUDYMASTER

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It's a highly ludicrous theoretical question, that doesn't matter.
 
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Originally posted by LadyMoon
oh geez ppl how are you going to find enough fuel to accelerate to close to the speed of g?
Accelerate to g? :p
 

deepulse

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Idea to ponder on:

If you're travelling at close to the speed of light, and you look at your own watch, its normal...if you look at somebody else's watch, its fast. BUT, if they look at they're watch, its normal, and if they look at your watch, its fast..

WHATS DOING ;)
 

Dangar

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Originally posted by deepulse
Idea to ponder on:

If you're travelling at close to the speed of light, and you look at your own watch, its normal...if you look at somebody else's watch, its fast. BUT, if they look at they're watch, its normal, and if they look at your watch, its fast..

WHATS DOING ;)

Not if you're in the same inertial frame of reference it's not, you wouldn't be able to tell the difference. And if it's an observer you'd have to look mighty quick to get a look at their watch whilst you flash by at the speed of light!
 

Rahul

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Originally posted by deepulse
Idea to ponder on:

If you're travelling at close to the speed of light, and you look at your own watch, its normal...if you look at somebody else's watch, its fast. BUT, if they look at they're watch, its normal, and if they look at your watch, its fast..

WHATS DOING ;)
relativity of simultaenity!
they are both correct.
simply becasue they are in different frames of reference.
relative to the person on earth, the person in the ship will be moving at relativistic speeds.
similarly, the person on the ship will see that the person on earth is moving at relativistic speeds 'the other way'.

put yourself into that situation. if you were in a train, which was stationary, and it started off. and there was another train parallel to you, would you say that you were moving forward or the other train was moving backwards? [of course you cant use the fact that you jerked back as it started:p]

ponder THAT!
Originally posted by Dangar
And if it's an observer you'd have to look mighty quick to get a look at their watch whilst you flash by at the speed of light!
hahah i dare someone to write that.
 

pseudo

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so that means u agree with me

ludicrous question? its theoretical phyisics einstien at his greatest
 
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LadyMoon

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seriously though how can you accelerate to the speed of c? with so much fuel.
(get out and push?)
even though i think the whole fourm is wrong, and is mislead. the theory is wrong.

having said that i cant seem to explain why so, but there is a flaw is your concept, becuase obviously Einestien was right and the millions ppl who are studying his concepts would have thought of this.

but this whole concept is wrong.
 
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ND

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Originally posted by LadyMoon
seriously though how can you accelerate to the speed of c? with so much fuel.
(get out and push?)
even though i think the whole fourm is wrong, and is mislead. the theory is wrong.

having said that i cant seem to explain why so, but there is a flaw is your concept, becuase obviously Einestien was right and the millions ppl who are studying his concepts would have thought of this.

but this whole concept is wrong.
What we are saying fits in with Einstein's theory of special relativity, it doesn't contravene it in any way.
 
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Originally posted by Under-stated

so if you are right then why hasnt this been thought of?
regardless of the limitations of current technology.
The reason it couldn't be utilized it because it takes a shitload of energy to reach a speed that would have even minimal effects on time. It's just not possible to get to those speeds, not just because they're very high speeds, but as you approach these speeds, mass increases, requiring greater energy, which increases more mass, which requires more energy etc.
 

Constip8edSkunk

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Originally posted by Under-stated
but, you dont have to approach the speed of light. The exponential increase in mass only happens at significant speed, close to the speed of light. i.e: 0.9c.
thus if you get to 0.5c then i dont think mass increase happens.
thats not true i dont think, mass increases even by small accelerations, like in a car, but only at such a minute level it is negligible. at 0.5 c, ur mass still increses about 15 percent i think
 
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ND

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Yeh it's not exponential, it'd be hyperbolic cos there is an asymptote at v=c.

edit: actually check out the equation, not a hyperbola, but it would like kinda like a disproportional one.
 

pseudo

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u r all missing the point the reason why we cannot move at this speed
a rocket can only accelerate at the same speed as the gases it exhausts
our current fuel powered rockets only expel gases at 20 000km/hr
u ppl take this way to serious it was just a hypothetical
 

John Howard

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Originally posted by pseudo

a rocket can only accelerate at the same speed as the gases it exhausts
our current fuel powered rockets only expel gases at 20 000km/hr
u ppl take this way to serious it was just a hypothetical
HAHAHAHA
do you mean to say that we can ACCELERATE at 20, 000 km/hr^2? (im assuming you mean that despite your typo).

do you know how fast that is? that a speed of the rocket is increasing at 20,000 km/h^2?

plus: i think you mean to say that the maximum velocity achieved by man in space/ the maximum SPEED of the rocket. and no its not 20,000km/h it is actually about 25600 km/h.

despite all that
ISNT THAT WHAT PEOPLE HAVE BEEN SAYING????
that it is impossible to accelerate to such a high speed???

-----
sorry to yell :p
 

xiao1985

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uhm, dunno if tis right but leme try do this:

the fuel should be used up simultaneously... okie, say there are m kg of fuel left on the ship, the person on the ship expericne time t... hence fuel is bein used up at the rate of m / t.........

however from an external observer, there will be m(v) kg of fuel (due to mass dilation) and they think time passes at t(v)......

usin the equation for time dilation and mass dialation:
m (v) = m (0) / sqrt [1 - v^2 / c ^2 ]

t (v) = t(0) / sqrt [ 1 - v^2 / c ^2 ]

hence m(v) / t (v) = m (0 )/ t(0)
hence the fuel is bein used up at a constant rate regardless of which initial frame of reference...... is this flawed?? cuz i dun feel very good abt this argument...... lolz
 

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