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Homework Help: Writing Gravitation Force On Central Sphere In Unit Vector Notation

  1. Nov 21, 2004 #1
    In Figure 13-34, a square of edge length 21.0 cm is formed by four spheres of masses m1 = 6.00 g, m2 = 3.00 g, m3 = 1.00 g, and m4 = 6.00 g. In unit-vector notation, what is the net gravitational force from them on a central sphere with mass m5 = 2.40 g?

    Well by using Newton's Law of Gravitation I get a single answer and I know it points towards m2 (or maybe i'm wrong). I just don't know how to write this in unit-vector notation.

    I did F={(6.67e-11 m^3/kg*s^2)(.0024kg)(.003kg-.001kg)}/{(.148m)^2}

    I get F=1.46e-14 N. I don't know if this is right, and if it is right I don't know how to put it in unit-vector notation.

    Nevermind figured it out :)

    Attached Files:

    Last edited: Nov 21, 2004
  2. jcsd
  3. Nov 21, 2004 #2
    Did you multiply by sin45/cos45 to get
    F = <1.034E-14, 1.034E-14> ?
    I was having the same difficultly...
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