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Lorentz Force

  1. Sep 14, 2010 #1
    Can anybody help me that how to work out the direction of Lorentz Force? Should I work out from the formula? Thanks.
  2. jcsd
  3. Sep 14, 2010 #2
    See thumbnail photo of an electron beam (~ 300 volts) being bent into a circle (~ 1 cm diameter arc) by a magnetic field (Helmholz coil). This is an undergraduate physics lab experiment for measuring the electron charge to mass ratio.

    Bob S

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    Last edited: Sep 14, 2010
  4. Sep 15, 2010 #3


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    The equation gives the directions.

    [tex] \mathbf{F} = q \left( \mathbf{E} + \mathbf{v}\times\mathbf{B} \right) [/tex]

    For a positive test charge there is an electric force in the direction of the applied electric field. There is also a force in the direction of the curl of the charge's velocity and the applied magnetic field. Together these define the Lorentz force.
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