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Determinging Gravity

  1. Nov 13, 2011 #1
    Sorry.. I think I posted this post already but I can't find the original thread..

    Two spheres of masses m = 1.00 g and m' = 1.00 * 10^2
    kg are isolated from all other bodies and are initially at
    rest, with their centers a distance r = 15.0 cm apart. One
    minute later, the smaller sphere has moved 0.534 mm
    toward the larger sphere. Compute the acceleration and
    the value of G.

    Acceleration: x = xi + Vxi(t) + (a)(t^2)/2

    0.149m = a(1s)^2/2
    a = (0.149m)(2) = 0.3 m/s/s

    Is this correct for acceleration?

    Could I have also used newtons second law some how to solve for acceleration?
    such as....
    F = (m1)(m2)(G)/.149^2 = 2.98*10^-11
    F = F1.... 2.98*10^-11 = (m1)(a)
    a = 2.98*10^-11/m1 = 2.9*10^-7

    But obviously these answers are not the same....

    Attached Files:

    Last edited: Nov 13, 2011
  2. jcsd
  3. Nov 13, 2011 #2
  4. Nov 13, 2011 #3


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