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Ah jebus [new]

  1. Aug 3, 2005 #1
    Alright, so I'm new here and don't really know the ropes. This question could go either in Astronomy, or here; but here is better since what I need involves an equation.
    So first a little about me: I'm new to this forum, and suck at maths. That is all.

    So maybe some clever mathematician among all of you could answer this question.
    If the system Alpha Centauri is around 4.35 light years away and a light year is 5,874,601,673,407.301 miles (while light travels at 299 792 458 miles per second), going at a speed of four hundred million miles per hour, how long it would it take to get to Alpha Centauri?

    I'm not sure how this will be taken, I know it confuses the bejebus out of me, so the key facts are:

    Alpha Centauri - 4.35 lightyears
    1 lightyear = 5,874,601,673,407.301 miles
    speed of light - 299 792 458 miles per second
    ship speed - 400 000 000 miles per hour

    If I left anything out, just say. As I say I'm not good at maths and so tend to leave out critical details, overlook them, or just plain screw them all up.
    This is for a story some friends and myself are working on, and I'm supposed to be the one who knows this stuff.

    Thanking you in advance,
    - Oxy
  2. jcsd
  3. Aug 3, 2005 #2
    If it helps, 4000000 mile/hour (mph) = 1,111.1111111 mile/second.
  4. Aug 3, 2005 #3


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    This goes in general physics, if not high-school homework.

    First get the distance to alpha centauri (in miles, I suppose)
    Then, use that and the speed of the ship (in miles per hour) to get the number of hours.
  5. Aug 3, 2005 #4
    I'd have thought it would end up in years. And this does seem more suited to maths, apply the numbers to a mathematically phrased question and they are no longer physics.
    Basically what I am saying is that the core of my question is numbers/maths, not physics. I'm giving you numbers for input, and I need an output of numbers.
  6. Aug 3, 2005 #5


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    x = 4.35 * 5.874 gazillion miles.

    v = x/t so t = x/v = 4.35 * 5.874 gazillion miles / 400 million mph = (4.35*5.874/400) zillion hours, where my definition of zillion is gazillion/million.
  7. Aug 3, 2005 #6
    The fact is light travels at about 186000 miles/sec. You are confusing kilometers. Another matter here, since you, oxymoron 02, tell us you are going about 1111 miles/sec, as a ratio to light this is around .0059, which would hardly effect:

    [tex]\frac{1}{\sqrt(1-(.0059)^2)}, [/tex]so that the relativistic factor would not be much, at least using my calculator.
    Last edited: Aug 3, 2005
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