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Homework Help: Mass Spectrometer (B-field)

  1. Oct 21, 2007 #1
    1. The problem statement, all variables and given/known data

    The problem can be found here;

    http://www.physics.uprm.edu/~mark/courses/FISI3172_I2007/PracticeExamIII.pdf [Broken]

    2. Relevant equations

    Ok, ok. I made some reaserch, and I found that the;

    radius of an ion orbit on a mass spectrometer = mv / qB

    where m = mass, v = velocity, q = charge, B = magnetic field.

    ok, now, if that holds true then;

    m = rqB / v


    3. The attempt at a solution

    so, the answers are the following;

    a) still don't know how the answer.

    b) increases

    c) increases

    d) decreases

    e) remain the same, since Temperature is not part of the equation, T will be a constant, and therefore the mass of the ions would stay the same?

    Can anyone verify this? And help me with the answer to A?
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Oct 21, 2007 #2
    Ok, ok. I made some reaserch, and I found that the;

    radius of an ion orbit on a mass spectrometer = mv / qB

    where m = mass, v = velocity, q = charge, B = magnetic field.

    ok, now, if that holds true then;

    m = rqB / v

    so, the answers are the following;

    a) still don't know how the answer.

    b) increases

    c) increases

    d) decreases

    e) remain the same, since Temperature is not part of the equation, T will be a constant, and therefore the mass of the ions would stay the same?

    Can anyone verify this? And help me with the answer to A?
     
  4. Oct 21, 2007 #3
    anyone?
     
  5. Oct 21, 2007 #4
    up..
     
  6. Oct 21, 2007 #5
    well, last try before i give up.
     
  7. Oct 21, 2007 #6

    hage567

    User Avatar
    Homework Helper

    For the first part, think about F = qv x B. How do you think you can determine the charge given this equation?
     
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