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Homework Help: Lorentz force part 1

  1. Apr 7, 2007 #1
    1. The problem statement, all variables and given/known data

    The motion of a charged particle P, observed in an inertial frame S. It is found that P moves with constant velocity v through a region of space where there is a uniform electric field E and a uniform magnetic field B. The speed v = |v|and the field magnitudes E = |E| and B = |B| are all non-vanishing.

    Use the Lorentz force law to express E in terms of v and B.

    2. Relevant equations

    Lorentz force formular-

    F=q(E+v*B)

    3. The attempt at a solution

    F=q(E+v*B)

    F/q = E+ v*B

    F/q - (V*B) = E
     
  2. jcsd
  3. Apr 7, 2007 #2

    marcusl

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    The charged particle is moving at constant velocity. What does that tell you about the force?
     
  4. Apr 8, 2007 #3
    constant velocity= no accelration , therfore no force

    F/q - (V*B) = E

    E= -v * B
     
  5. Apr 8, 2007 #4

    marcusl

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    You got it!
     
  6. Apr 8, 2007 #5
    anyone else can confirm if my answer is correct
     
  7. Apr 8, 2007 #6
    looks okay.
     
  8. Apr 8, 2007 #7

    marcusl

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    You don't trust me, imy786?
     
  9. Apr 9, 2007 #8
    Its correct.
     
  10. Apr 9, 2007 #9
    its that i dont trust u.....anyone can say its correct...without any justification...

    and as you havnt got a homework helper badge.....its harder to belie...

    it doesnt mean i dont belive u..

    thanks for your help
     
  11. Apr 9, 2007 #10
    He justified it. If it makes sense to you, then that should be enough to at least turn it in.
     
  12. Apr 9, 2007 #11

    marcusl

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    No worries.

    Thanks for the backup, StatMechGuy...
     
    Last edited: Apr 9, 2007
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