• We have a few events lined up for the October school holidays!
    Watch this space...

Length Contraction Question 0.99999c answers (1 Viewer)

whitnall8

Member
Joined
Feb 19, 2009
Messages
151
Gender
Male
HSC
2010
What did people get for part a) and b) of the length contraction question?
 

astroe

Member
Joined
Mar 16, 2008
Messages
691
Location
Sydney.
Gender
Male
HSC
2009
I forgot part a) but for part b) I got like 750/760 years or something like that, forgot too.
 

abhi23

Coming to the Toga Party?
Joined
Jan 16, 2008
Messages
366
Gender
Male
HSC
2009
yep i got 760 light years.
 

darkchild69

Nanotechnologist
Joined
Sep 6, 2006
Messages
236
Location
Sydney
Gender
Male
HSC
2001
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
 
Last edited:

slamduncs

New Member
Joined
Sep 16, 2008
Messages
25
Gender
Male
HSC
N/A
So it is 760. I hope I wrote that and I'm remembering 726 for some weird reason.
 

M@ster P

Member
Joined
Feb 9, 2008
Messages
619
Gender
Male
HSC
2009
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
 
Last edited:

youngminii

Banned
Joined
Feb 13, 2008
Messages
2,093
Gender
Male
HSC
2009
Lol I did 2.4 * 10^10 seconds.. which ends up being 760 years
Yaaaay
 

carlytse621

Member
Joined
Feb 7, 2008
Messages
210
Location
Behind you ;)
Gender
Female
HSC
2009
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

Member
Joined
Feb 7, 2008
Messages
210
Location
Behind you ;)
Gender
Female
HSC
2009
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

...
Joined
Mar 26, 2008
Messages
2,049
Location
Guess
Gender
Male
HSC
2009
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.
 
Last edited:

Aerath

Retired
Joined
May 10, 2007
Messages
10,178
Gender
Undisclosed
HSC
N/A
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

Nanotechnologist
Joined
Sep 6, 2006
Messages
236
Location
Sydney
Gender
Male
HSC
2001
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

Member
Joined
Nov 24, 2008
Messages
128
Gender
Male
HSC
2009
Ahh crap,
i wrote b) in light years, instead of years.....
Oh well stupid mistake. Hopefully they wouldnt mind ^^
 

123huss123

New Member
Joined
Feb 20, 2008
Messages
13
Gender
Male
HSC
2010
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
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top