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Electron moving in a magnetic field

  1. Jan 14, 2010 #1
    1. The problem statement, all variables and given/known data
    how will an electron move if it is launched into an magnetic field at an angle of 45o (w/ respect to the magnetic field)

    2. Relevant equations
    F=q*v X B

    3. The attempt at a solution
    I'm having a hard time picturing what is going on. I know that if the electron is perpendicular to the magnetic field, then it will go around in a circle. I'm thinking that the electron will make and elipse
  2. jcsd
  3. Jan 14, 2010 #2
    Try to think of it like this: there are two velocity components (one along the direction of the magnetic field and one perpendicular to the magnetic field). The component perpendicular to the magnetic field will allow for an acceleration that is perpendicular to that particular velocity; the component parallel to the magnetic field results in no acceleration and so that velocity component remains unaffected.
  4. Jan 14, 2010 #3
    so it will look like a spring/slinky? because the part that isn't affected (perpendicular) with make a circle while the other one won't be affected and will therefore go in a straight line
  5. Jan 14, 2010 #4
    Yup...spring, slinky, spiral...all the sort.
  6. Jan 14, 2010 #5


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    Homework Helper

    The mathematical term for this shape is a helix.
  7. Jan 14, 2010 #6
    thanks so much!
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