metalicarulez
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ok all i can think of this is... the cost involved
i don't know wot else to write coz im given 3-4 lines to answer
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small question on space travel (1 Viewer)
- Thread starter metalicarulez
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i don't know wot else to write coz im given 3-4 lines to answer
Ragerunner
Your friendly HSC guide
Because your moving at the speed of light, mass will increase as a result of relativity.
As mass increases, the energy required by the spaceshuttle would need to increase in order to keep the shuttle moving as shown by einstein's famous equation E = MC^2
Which means an extreme amount of fuel is required that is impossible to get at this present time, which leads to the high costs involved.
As mass increases, the energy required by the spaceshuttle would need to increase in order to keep the shuttle moving as shown by einstein's famous equation E = MC^2
Which means an extreme amount of fuel is required that is impossible to get at this present time, which leads to the high costs involved.
Constip8edSkunk
Joga Bonito
consider the mass dilation function:
m_v = m_o / sqrt [ 1 - (v/c)^2 ]
as you can see, when v approaches c; the relativistic mass, 'm_v', approaches infinity. this would therefor require an energy input of infinty (E=mc^2), which is clearly impossible. Hence, one can never reach the velocity of c.
m_v = m_o / sqrt [ 1 - (v/c)^2 ]
as you can see, when v approaches c; the relativistic mass, 'm_v', approaches infinity. this would therefor require an energy input of infinty (E=mc^2), which is clearly impossible. Hence, one can never reach the velocity of c.
:: ck ::
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wot ?! theres a mass dilation equation
or is that supposed to be time dilation?
edit : nvm found it
http://www.utdallas.edu/~parr/chm5414/54140903.html
is mass dilation in our syllabus?
or is that supposed to be time dilation?
edit : nvm found it
http://www.utdallas.edu/~parr/chm5414/54140903.html
is mass dilation in our syllabus?
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Xayma
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Actually its more then just an extreme amount of fuel, since as you travel faster you need more fuel which therefore requires a greater mass, which will never reach the speed of light because the mass of fuel will then become infinite. It will become asymptotic to that line though. Of course there are theories of a "warp bubble" star trek style idea.
Ragerunner
Your friendly HSC guide
And it's also in the formula sheet =)
Not exactly. This notion of ``relativistic mass'' increasing with velocity was rejected by Einstein and subsequently by all modern physicists. The fictitious relativistic mass m<sub>r</sub> was first introduced so that one could write the equations of motion of relativistic particles in Newtonian form using f<sup>i</sup> = m<sub>r</sub>a<sup>i</sup> where m<sub>r</sub> increases with velocity and i runs values of 1,2,3. Later study found that m<sub>r</sub> was an absolutely useless quantity that plays no role in any physical equation. The correct form is F = dP<sup>u</sup>/dt<sub>0</sub> where P<sup>u</sup> = m<sub>0</sub>U<sup>u</sup> is the 4-momentum, U<sup>u</sup> = dx<sup>u</sup>/dt<sub>0</sub> is the 4-velocity, x<sup>u</sup> = (cx<sup>0</sup>, x<sup>1</sup>, x<sup>2</sup>, x<sup>3</sup>) is 4-position, m<sub>0</sub> is the ``invariant'' rest mass, d/dt<sub>0</sub> denotes the derivative with respect to proper time and u runs values of 0,1,2,3 with time being the 0th dimension. The relativistic analog of Newton's second law is thus F<sup>u</sup> = m<sub>0</sub>A<sup>u</sup>, A<sup>u</sup> = dU<sup>u</sup>/dt<sub>0</sub> is the 4-acceleration. It can be seen from this derivation that ``relativistic mass'' varying with velocity is not the correct reason why accelerating a spacecraft to the speed of light is an impossibility. The correct explanation is that a given force produces a diminishing coordinate acceleration as the speed approaches c.
Edit: It occured to me that my previous explanation wasn't as clear as it could be, so I have revised it.
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Rahul
Dead Member
when i called up the hsc advice line, and asked about mass dilation. they said you just need to know its effect.
in other words, the 'what' and not the 'why'...
in other words, the 'what' and not the 'why'...
Ragerunner
Your friendly HSC guide
What the gay? I didn't understand that but oh well
Ragerunner
Your friendly HSC guide
But that is not required by the syllabus?
...
^___^
in this case, its not undefined rather infinity
thats one rule of dividng by 0..either undefine or infinity
Xayma
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It doesnt really matter since you arent going to reach it anyway. If you do limits it does approach infinity though.
Of course there is a way to avoid travelling at the speed of light and thats through wormholes etc. http://omnis.if.ufrj.br/~mbr/warp/ but this is outside the scope of the syllabus but interesting to know.
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Please note however that relativistically increasing mass is not a real physical phenomena, merely a mathematical tool used to make certain equations of motion look more Newtonian. It is an entirely obsolete and useless quantity in light of the modern 4-space approach in which mass is invariant. The fact that relativistic mass is a mandatory part of the HSC syllabus indicates a deep-rooted problem with the physics department of the board of studies.
...
^___^
dunno if this is true
the mass is increased to infinity..hence u need infinite amount of energy to make the object reach the speed of light..hence u can never get to speed of light, or else :\
the mass is increased to infinity..hence u need infinite amount of energy to make the object reach the speed of light..hence u can never get to speed of light, or else :\