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Homework Help: Canter of mass and its speed

  1. Nov 19, 2005 #1
    Center of mass and its speed

    hi,I'm not shure if this belongs in math section or here

    The center of mass is special point in body and is moving as if whole mass was in it.

    Velocity of center of mass V(C)= ( m1*v1 + m2*v2... )/(m1 + m2...)

    V(c) is in a way an average speed of all the individual speeds bodies in the system have. Value of V(C) depends most on the mass of individual objects in a system. If system contains one very massive body and several others with small mass, then value of V(c) will be very close to the speed of a body with large mass.

    It does make some sense,but I'm looking at formula
    V(C)= ( m1*v1 + m2*v2... )/(m1 + m2...) and can't figure out how does that work out in this formula. If M1 has very large mass and speed V1 smaller approx. by factor 100 from speeds of other bodies, why would formula for V(C) give result that is closer to V1 than say to V2 and V3 ?

    thank you in advance
    Last edited: Nov 19, 2005
  2. jcsd
  3. Nov 19, 2005 #2


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    Homework Helper

    It might help to think about it this way: What happens to the center of mass when the mass of the lighter object goes to zero?
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