Length Contraction Question 0.99999c answers (1 Viewer)

whitnall8

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What did people get for part a) and b) of the length contraction question?
 

astroe

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I forgot part a) but for part b) I got like 750/760 years or something like that, forgot too.
 

abhi23

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yep i got 760 light years.
 

darkchild69

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The nearest galaxy to ours is the Large Megallanic Cloud, with it's centre located 1.7x10^5 light years from Earth. Assume you are in a spacecraft travelling at a speed of 0.99999c towards the Large Megallanic cloud.

a) In your frame of reference, what is the distance between Earth and the large Megallanic cloud?

760.26ly

b) In your frame of reference, how long will it take you to travel from Earth to the Large Megallanic Cloud

760.27years

I reckon more than anything they will be very picky about units
 
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slamduncs

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So it is 760. I hope I wrote that and I'm remembering 726 for some weird reason.
 

M@ster P

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The nearest galaxy to ours is the Large Megallanic Cloud, with it's centre located 1.7x10^5 light years from Earth. Assume you are in a spacecraft travelling at a speed of 0.99999c towards the Large Megallanic cloud.

a) In your frame of reference, what is the distance between Earth and the large Megallanic cloud?

760.26ly

b) In your frame of reference, how long will it take you to travel from Earth to the Large Megallanic Cloud

760.27years

I reckon more than anything they will be very picky about units

fuck i got both of them right, but the second one I put light years!!!!!!!!!!!!!!!, so yeah 1 mark down the drain, I swear these calculations are what gonna differentiate the students there is so much to consider, you have to put the right units for your answer, convert cm into m, g into kg.........then you have get the right method, get the right answer....................when i was doing them i had to change my working like 3 times cause i forgot to change the units
 
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youngminii

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Lol I did 2.4 * 10^10 seconds.. which ends up being 760 years
Yaaaay
 

carlytse621

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for the first one I got a bigh number of distance coz i times c , so my unit is meter (but if u changed back to light year it will be 7xx light years too), will that be alright? :S
the second i got 7xx ......but damn! i put in second insetad of years :( 1 mark gone~
 

carlytse621

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i did: length(v) = length(o) square root blablabla
but for length(o), I sub the original distance (something light year) times c
so i end up with a huge number
but on the second part u need to times c in the answer in part 1 as well....
so balance everythign all....
hmmmm....my explanation here is so confuse lol
 

shaon0

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The nearest galaxy to ours is the Large Megallanic Cloud, with it's centre located 1.7x10^5 light years from Earth. Assume you are in a spacecraft travelling at a speed of 0.99999c towards the Large Megallanic cloud.

a) In your frame of reference, what is the distance between Earth and the large Megallanic cloud?

760.26ly

b) In your frame of reference, how long will it take you to travel from Earth to the Large Megallanic Cloud

760.27years

I reckon more than anything they will be very picky about units
I got the first one correct but the 2nd one incorrect.
 
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Aerath

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The nearest galaxy to ours is the Large Megallanic Cloud, with it's centre located 1.7x10^5 light years from Earth. Assume you are in a spacecraft travelling at a speed of 0.99999c towards the Large Megallanic cloud.

a) In your frame of reference, what is the distance between Earth and the large Megallanic cloud?

760.26ly

b) In your frame of reference, how long will it take you to travel from Earth to the Large Megallanic Cloud

760.27years

I reckon more than anything they will be very picky about units
Do you reckon they'll accept 760 light years and years? Cause I left mine to 2 sf. =( Cause, otherwise it looks like my answers are just the same, with only a change in units.
 

darkchild69

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Do you reckon they'll accept 760 light years and years? Cause I left mine to 2 sf. =( Cause, otherwise it looks like my answers are just the same, with only a change in units.
If I was marking it, I wouldn't. Simply due to the number of sig figs in the velocity.

But, I'm a prick when I mark stuff... And ONLY then ;)
 

mR sinister

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Ahh crap,
i wrote b) in light years, instead of years.....
Oh well stupid mistake. Hopefully they wouldnt mind ^^
 

123huss123

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this is a pretyy retarded question but for somee weirdddddddddd reason i got the answer in light yearss i got 2.53 x 10^-6 light yearsss but if u convert that to seconds u still get same asnwer i thinkk ? wud u still get full markss
lma00 sadddd forr evenn thinkingg bout ittt hsc is overrrrrrr wtf
 

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