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Time it take for small objects to come together under gravity

  1. Jan 25, 2007 #1
    Hey everyone!!

    I've done http://www.fourmilab.ch/gravitation/foobar/" [Broken] and i find it interesting how objects of any mass just randomly attract each other. Anyway, i always wanted to find out how long it should take for a mass in this experiment to gravitate towards the other. The problem is it isn't like doing it on earth where at the surface everything accelerates at 9.8m/s. The only relevant equation for acceleration in this case would be
    m=mass in grams
    r=distance in cm
    I just learned a LITTLE calculus but so far i can only calculate how long it will take for an dropped object to hit the ground. I was hoping i could use this but since the acceleration is always changing i don't know how to do this out. Can someone help??

    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Jan 25, 2007 #2


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    Gold Member

    Hi hover,

    Really? Where you expecting them to repel each other :biggrin:

    So you want to complicate things more with non constant acceleration I see. I dont know the extent of your calculus knowledge, but this involves integrating the acceleration function.

    http://www.sunybroome.edu/~biegen_j/phys1/modules/varacc/Mod4_3.htm [Broken]

    I recommend for situations like this, you should use constant acceleration and find the time like you would normally.
    Last edited by a moderator: May 2, 2017
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