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Constant speed of light (1 Viewer)

Rorix

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Instantaneous action at a distance owns Special Relativity.:(
 

Wohzazz

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Originally posted by Xayma
You have plenty of options.. ever thought about Engineering?

No i haven't..is it a lot of practical? And what kind of UAI are we looking at here
Originally posted by abdooooo!!!
abdooooo!!! = 04er

abdooooo!!! = failure at chem... crappy band 6... im repeating it LOL... it'll be funny if i get a band 5 second time around... hahaha that'll be the end of abdooooo!!!
omg your accelerated... then your are pro even if you got low band 6.
i don't know about accelerated, so when did you learn your preliminary stuff? last year, last year? what subjects did you accelerate
Originally posted by abdooooo!!!

i want to do med man... med!!! or adv science at usyd. enginering could be good, and economics (math version) would good as well.
well good luck with that, i doubt i get a UAI to choose that

Originally posted by abdooooo!!!

by the way im doing bio, chem, phy, 4u math, 3u english, and philosophy this year. my physics is crap, i prefer biology and chemistry combo. but math is my strength area...
same though i never do good in those math comps..maybe only because relatively.., its my strength:)
Originally posted by abdooooo!!!

hey Wohzazz, its not you don't understand science very well... its just that there are some real freaks and nerds on this forums. :p

the questions you ask are pretty hardcore... most of them are first year uni level, i think. so don't worry... you'll do fine. you'll never know in 10 month you might top the state in science...
i never knew i was stepping over the threshold to university level...i was just thinking of them when i'm reading

as for topping the state....nowway, maybe you or Xayma considering your know so much already...
 

Xayma

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No I doubt either of us will top it, we cant write a 5 page essay on the contribution of the quark towards society ;). I doubt zeropoint will either (is he even an '04er) he will probably go off on a tangent and spend the test explaining why the question is wrong.

I dont do good in the maths comp either, the only ones I do good at are Chem comp and Geog Comp.
 
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Wohzazz

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Originally posted by Xayma
No I doubt either of us will top it, we cant write a 5 page essay on the contribution of the mole towards society ;).

I dont do good in the maths comp either, the only ones I do good at are Chem comp and Geog Comp.
Heh you serious? They tell you to write that? What module, thought that was preliminary? i can write 4 lines on how calculations of chemist are made easier because the mole universal unit

Chem comps are alright, but geog comps...nope i can't read a map.
 

abdooooo!!!

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Originally posted by Xayma
I doubt zeropoint will either (is he even an '04er) he will probably go off on a tangent and spend the test explaining why the question is wrong.
ahahaha. so true. zeropoint talks too funny... the markers will proly not understand anything he writes. all zeros. :p
 

Xayma

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Originally posted by Wohzazz
Heh you serious? They tell you to write that?
I wouldn't be surprised in the HSC.

Originally posted by Wohzazz
Chem comps are alright, but geog comps...nope i can't read a map.
I can read a map, but geog comps are just easy (3HD's/3), Chem comps easy as well (3HD's 1 D and 1 Excellence/5), its English that sucks (1 Credit 1 participation/2) and Maths and Science are just D's.

And the cost is too much.
 

abdooooo!!!

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im a pro at math comp... LOL. nah... them comps are too hard... high distinctions is the only thing i get the whole time... grrr... why couldn't i get a cash prize dammit.
Originally posted by Wohzazz
omg your accelerated... then your are pro even if you got low band 6.
i don't know about accelerated, so when did you learn your preliminary stuff? last year, last year? what subjects did you accelerate
accelerating is nothing... i never even done the prelim course... i just went to the teacher at the start of year11 and said give me a year11 test and i'll prove to you im good enough. none of the teachers let me... except for the chem teacher... so i got accelerated and started year12 straight off. :)
 

Wohzazz

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But those kind of societal question they have one as like the longer-essay responce type question at the end.....just write facts and know what to include
 

Wohzazz

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Originally posted by abdooooo!!!

accelerating is nothing... i never even done the prelim course... i just went to the teacher at the start of year11 and said give me a year11 test and i'll prove to you im good enough. none of the teachers let me... except for the chem teacher... so i got accelerated and started year12 straight off. :)
that's amazing..what was your actual mark, you must of hammered a lot of yr 12s
 

Xayma

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Originally posted by abdooooo!!!
im a pro at math comp... LOL. nah... them comps are too hard... high distinctions is the only thing i get the whole time... grrr... why couldn't i get a cash prize dammit.
Only High Distinctions Im stuck here with my Distinctions... getting an excellence for Chemistry results in a little gay plaque thing, waste of money.
 

abdooooo!!!

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Originally posted by Wohzazz
that's amazing..what was your actual mark, you must of hammered a lot of yr 12s
whats amazing? all i did was memorise the hard issues like pollutions and WW1 and others didn't memorise it that well i guess... but my school sucks... i only got 90 (really low band 6) for comming first in chemistry at school. :(

but you'll never know i applied for a re-check... hahaha... i might get lower.

edit: i proly lost 5 marks because i didn't write enough... due to my slow and poor handwritting... and made i think 1 silly mistake. the rest of the marks i lost is proly due to just hardcore marking. :mad:
 
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Wohzazz

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LOL,but you did come first..someone in your school would of killed to get your mark

This question doesn't make much sense

If our galaxy, the Milky Way, is 65000 light-years in radius, how fast would a spacecraft need to travel so that its occupants can travel across it in 45 years?
SO we use:
t (v)= t(o)/ sqroot (1-v^2/c^2)

I subbed t(v)= 65000 t(o)= 45 and i got the answer
But weird thing is, light years is not time but is distance
so i figured that what i did was finding a factor of the times, but then i'm assuming the spacecraft is travelling at the speed of light in the first place...weird
 

Wohzazz

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LOL,but you did come first..someone in your school would of killed to get your mark

This question doesn't make much sense

If our galaxy, the Milky Way, is 65000 light-years in radius, how fast would a spacecraft need to travel so that its occupants can travel across it in 45 years?
SO we use:
t (v)= t(o)/ sqroot (1-v^2/c^2)

I subbed t(v)= 65000 t(o)= 45 and i got the answer
But weird thing is, light years is not time but is distance
so i figured that what i did was finding a ratio of the times, but then i'm assuming the spacecraft is travelling at the speed of light in the first place...weird
 

abdooooo!!!

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Originally posted by Wohzazz
This question doesn't make much sense

If our galaxy, the Milky Way, is 65000 light-years in radius, how fast would a spacecraft need to travel so that its occupants can travel across it in 45 years?
SO we use:
t (v)= t(o)/ sqroot (1-v^2/c^2)

I subbed t(v)= 65000 t(o)= 45 and i got the answer
But weird thing is, light years is not time but is distance
so i figured that what i did was finding a factor of the times, but then i'm assuming the spacecraft is travelling at the speed of light in the first place...weird
LOL. something bad happened to the forum...

hey you did it wrong... i think. 65000c is strictly distance and not time, you need to divide by the speed of the of the craft which is x/c because its an unknown, this is how i would set it out:

65000/(x/c) = 45 * root (1- (x/c)^2)

if you solve it which i did using quadratics... you get something like 2.9789... * 10^8. i used the c = 3.0*10^8 so results could vary depending on what you consider speed of light to be. so its only a little under the speed of light... :p

edit: how do you do it by just assuming T (v) as 65000... i tried that way, it seem to produce an complex result for me which is not real and positive which is needed for all physics answers. :)
 
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Xayma

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Umm that question was asked before.

I solved it doing simulatenous equations. Really annoying just search the forums. Or abdoo can just solve it above me. Or maybe not. I will give you a clue, it gives you the radies, but to go across the galaxy requires you to travel the diameter.

Ok using the formula t=t_0/rt(1-v^2/c^2)
Since Time=distance/speed
t=1.230719443x10^21/v (I converted to SI units, I wasnt getting the answer any other way) (oh yeah the distance across is 130 000light years as 65 000 is the radius) anyway let 1.230719443x10^21=R

t_0=1420060896seconds
let t_0=E
And c^2=9*10^16ms^-1

therfore we get R/v=E/sqrt(1-v^2/(9x10^16))
Rsqrt(1-v^2/9x10^16)=Ev (cross multiplying)
R^2-(R^2xV^2)/(9x10^16)=E^2v^2 (squaring)
R^2=(R^2xV^2+(9x10^16xE^2xV^2))/9x10^16 (getting v^2 on one side)
9x10^16xR^2/(9x10^16xE^2+R^2)=v^2
Then calculator job to get 299 999 982ms^-1 or 0.99999994c

Bit messy but yeah. Yay I get to do this next year when we start relativity :(
 
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abdooooo!!!

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wait i think... i miss read the question wrote down the number in the wrong way... hahaha. but still it doesn't matter same results produced.

yeah you can just assume it and do it like that Wohzazz and get some sort of close answer... but thats the wrong way of doing it. :p

Originally posted by Xayma
Umm that question was asked before.

I solved it doing simulatenous equations. Really annoying just search the forums. Or abdoo can just solve it above me. Or maybe not. I will give you a clue, it gives you the radies, but to go across the galaxy requires you to travel the diameter.
what is this? hahaha... trick question.... shit. hahaha
 

Xayma

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It wasnt the same results. You used the radius when you should of used the diameter, so you ended up with results that were tens of thousands of kms^-1 out.

Originally posted by abdooooo!!!
what is this? hahaha... trick question.... shit. hahaha
Well I posted, then I saw you had posted in that time frame, so I editied it, then I realised that you made a mistake *shock*.
 

abdooooo!!!

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Originally posted by Xayma
It wasnt the same results. You used the radius when you should of used the diameter, so you ended up with results that were tens of thousands of kms^-1 out.
no i wasn't saying that... i know the radius thing... i was talking about the T (v) and the T (o) thing... i swapped them two around when i was writing them down for some reason i think... :p
 

Xayma

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If you knew the radius thing why did you put it in the equation when the diameter was required?
 

abdooooo!!!

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Originally posted by Xayma
If you knew the radius thing why did you put it in the equation when the diameter was required?
nooo... i knew it after you've enlightened me to the fact Xayma!!! why would they trick you like that??? i suffer many mistakes under oddly worded question that is there to trick you... :p
 

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