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Did Anyone Get Confused By The Wording Of The Time Dilation Question (1 Viewer)

walla

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"i'm not arguing that 16.7 is the correct answer, i'm arguing that BOS fucked the question, and that 16.7 is the answer that they'll mark correct."

the BOS won't give marks for something that is wrong, when it can be answered correctly using expected knowledge from the syllabus.
 

~TeLEpAtHeTiC~

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Originally posted by Bannanafish
ok ok

EXPLANATION!!!

Acceleration of the spaceship, taking time for the astronaut to "see" the clock on earth, and any other "complications" are all irrelivant. This is a THOUGHT experiment, hence ignoring all these factors. Hell, if it weren't i'd argue how the hell could the astronaut see a clock so far away?? Also in Einstein's THOUGHT experiment, he never said anytihng about acceleration (which is obviously needed for his trains to travel so fast).

So since we can ignore all these things, think of the spaceship as a train.
Train is travelling at 0.8c
Goes past an observer
Observer looks in the window of the train and the clock inside is running slow (i.e. for every second on his watch, the clock is only going a fraction of a second)
The passenger on the train looks at the observer's watch and sees it as going slow (i.e. for every second on his clock, the watch is only going a fraction of a second)
If the observer sees something to take 10 seconds according to his watch, then he sees the clock inside the train go 6 second.
If the passenger sees something to take 10 seconds according to his clock, then he sees the watch on the observer to go 6 seconds.
Now if 10 seconds was 10 years, the PASSENGER'S clock READS 10 hours. THIS IS WHAT THE QUESTION GAVE YOU.
Now the PASSENGER looks at the OBSERVERS watch. THIS IS THE PERSPECTIVE THE QUESTION ASKED.
Therefore the OBSERVERS watch would say 6 years have passed.

Now if you can't understand this, i don't see how you can argue.
good explanation banana TOO BAD ITS D..
..
..
..
lol joks mate
nah i understand its b
just wish it was d..but my reasonaing at the time was off..i did multi chioce last..

hopefully markers get just as confused...
good luck ppl
 

Bannanafish

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hahhaah so do i... so do i...
i put d :( also did multi last, was stressing (even though i had 20min to do it)
 

~TeLEpAtHeTiC~

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i finish everything with 40 mins to go..lol
so i went back to option, and rewrote my answers neatly...
and then wentover all my short answer questions
and then looked over multichoice one last time
(and then missed that fucking question obut step down transformers i still had 1:25 damn it!!)
but i agree with something B.rabbit said earlier...

Originally posted by B. rabbit
that 25:1 question... Thats so FUCKING STUPID... WHY THE #@%did they state the whole question in primary:secondary then for answer make it secondary to primary ??? WTF is the point seriously... i worked all the shit out and got it wrong by putting 1:25 aswell... thx BOS u dumb fucks test physics not how carefully we examine EACH WORD in a question... BLEED BITCH BLEEEEEED[/B]
although not as frustrated as him..lol...i still feel its not an english exam.. stupid question...
meh all good
 

Bannanafish

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yeah that's very true...but i guess these days people doing physics do end up doing law and not science/engineering :(
 

LadyMoon

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Originally posted by Bannanafish
ok ok

EXPLANATION!!!

Acceleration of the spaceship, taking time for the astronaut to "see" the clock on earth, and any other "complications" are all irrelivant. This is a THOUGHT experiment, hence ignoring all these factors. Hell, if it weren't i'd argue how the hell could the astronaut see a clock so far away?? Also in Einstein's THOUGHT experiment, he never said anytihng about acceleration (which is obviously needed for his trains to travel so fast).

So since we can ignore all these things, think of the spaceship as a train.
Train is travelling at 0.8c
Goes past an observer
Observer looks in the window of the train and the clock inside is running slow (i.e. for every second on his watch, the clock is only going a fraction of a second)
The passenger on the train looks at the observer's watch and sees it as going slow (i.e. for every second on his clock, the watch is only going a fraction of a second)
If the observer sees something to take 10 seconds according to his watch, then he sees the clock inside the train go 6 second.
If the passenger sees something to take 10 seconds according to his clock, then he sees the watch on the observer to go 6 seconds.
Now if 10 seconds was 10 years, the PASSENGER'S clock READS 10 hours. THIS IS WHAT THE QUESTION GAVE YOU.
Now the PASSENGER looks at the OBSERVERS watch. THIS IS THE PERSPECTIVE THE QUESTION ASKED.
Therefore the OBSERVERS watch would say 6 years have passed.

Now if you can't understand this, i don't see how you can argue.
Hang on!
According to this:
"If the observer sees something to take 10 seconds according to his watch, then he sees the clock inside the train go 6 second.
If the passenger sees something to take 10 seconds according to his clock, then he sees the watch on the observer to go 6 seconds."

So say the astronaut travells to a distant planet at the speed of 0.8c and it takes him 10 years (relative to him). According to your explanation he would look out the window, look at the clock on Earth and see it show only 6 years....ok?
Now the astronaut comes back to Earth, suppose he doesnt land yet he looks at the clock on Earth, and again according to your explaination, he should now see the clock on earth show 12yrs. And the onboard clock on the space craft 20yrs.

Here comes the good part!
Now the astronaut gets out of the spacecraft and lands on earth! So according to the twin paradox the Time on Earth is actually faster than the time on the spacecraft.
So you are actually saying that when the astronaut gets out of the spacecraft and looks at the clock on Earth he sees it as 33.33 years????

LOL
Your explanation is funny! :p
 

Bannanafish

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hahah the point is he doesn't land on earth, if he did then the earths inertial frame takes preference etc.

i.e. if he doesn't return, both inertial frames's observations are as valid as the other, if he does return, the earths frame takes preference
 

Bannanafish

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i dunno, cause i don't understand general relativity
about 2 people in the world probably do, go ask them
 

LadyMoon

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Oh well its no use discussing this now....lets just wait to see what the "big heads" at the Board are going to say. Who knows it might even preposterously end up being "A" according to them!
 

~TeLEpAtHeTiC~

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Originally posted by Bannanafish
i dunno, cause i don't understand general relativity
about 2 people in the world probably do, go ask them
1 of them is dead (einstien)
the other cant talk or walk (hawlkings)
see how dangerous trying to coprehend general relativity can be :S


:p
 

freaking_out

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look we'll just have to wait until the standard packages/markers guidelines come out...until then we can't do anything abt. it.


but i do think it was B, and not like what i got:- D
 
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ND

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Originally posted by walla
"i'm not arguing that 16.7 is the correct answer, i'm arguing that BOS fucked the question, and that 16.7 is the answer that they'll mark correct."

the BOS won't give marks for something that is wrong, when it can be answered correctly using expected knowledge from the syllabus.
The fact is that he accelerated, and therefore left the inertial frame of reference. Whether BOS see it that way... i dunno.
 
N

ND

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Originally posted by freaking_out
look we'll just have to wait until the standard packages/markers guidelines come out...until then we can't do anything abt. it.


but i do think it was B, and not like what i got:- D
Somehow i think we'll be over it by then. :p
 

toknblackguy

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what would truly be funny is if the answer was c - 10 years!
they come out with some shat saing accelerating and declerating so the whole time dilation thing doesn't hold, even though the question says at constant 0.8c
:p
 

freaking_out

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Originally posted by ND
Somehow i think we'll be over it by then. :p
yeah, but i mean to answer the debate goin' on this thread...the only way is to wait!!...unless u wanted to take it to a university professor...who'll definitly say B. :D
 

Adam

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No way :p

Without reading all the crap that they put in it, they are basically asking much time has passed on earth, when 10 years have passed on the spaceship. The people on earth are older, regardless of what frame you look at it from, therefore more time has passed on earth.
 

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