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Homework Help: Magnetic fields ahhh!

  1. Feb 26, 2004 #1
    Here's my problem:

    A particle with charge 4.5E-19 C travels in a circular orbit with radius .465 m due to the force exerted on it by a magnetic field with magnitude 1.7 T and perpendicular to the orbit.

    a) What is the magnitude of the momentum p of the particle?
    I used the equation R=(mv)/(qB) and calculated mv (linear momentum) to be 3.6E-19 kg*m/s.

    b) What is the magnitude of the angular momentum L of the particle?
    Herein lies the rub! Angular momentum = v/R = qB/m
    I don't know velocity or mass independently, only their product (mv). So how do I calculate angular momentum?

    Thanks for any help!
     
  2. jcsd
  3. Feb 27, 2004 #2
    Double-posting is annoying.
     
  4. Feb 28, 2004 #3
    Angular momentum of a particle moving in a circular motion about the centre is : mvr = pR
     
  5. Feb 28, 2004 #4
    a) Only God knows

    b) The hell would I know
     
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