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Homework Help: Colliding spheres

  1. Oct 16, 2006 #1
    Ive got this one homework problem that i am totally clueless on. Any help?
    "Two insulating spheres having radii 0.34 cm and 0.54 cm, masses 0.13kg and 0.58 kg, and charges -3x10^-6 C and 2x10^-6 C are released from rest when their centers are seperated by 1.2m.

    How fast is the smaller sphere moving when they collide? Answer in units m/s."
  2. jcsd
  3. Oct 16, 2006 #2
    The professor sent a message stating this. But he has not gone over any of these and i have searched the book for them.

    It involves the use of the conservation of the total energy and momentum; set up equations for the initial total energy (kinetic plus electrical potential energy) and momentum and the final total energy and momentum at the moment of collision. Solution of these equations should provide the answer to the question raised.
  4. Oct 16, 2006 #3
    Indeed you have to use those methods, but how far have you gotten so far in trying to solve them?
  5. Oct 16, 2006 #4
    To be honest nowhere. My textbook is divided up into two parts. I have part 2 for physics 2 and those equations are in the first part. Its been over a year since i have taken phys 1 and i cant remember those formulas.
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