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Motion of point charges in electronic fields

  1. Aug 31, 2004 #1
    An electron starts at the position (0,0) with an initial velocity 5,000,000 m/s at 45 degrees angle to the x axis. THe electric field is in the positive y direction and has a magnitude of 35000 N/C. At what location will the electron strikes?

    Please help me setup this problem.
  2. jcsd
  3. Aug 31, 2004 #2


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    You really just have to think of this the same way you think of a projectile motion problem (an object acting under the influence of gravity.) The force on the electron is always down within the uniform electric field. This means the electron will strike somewhere on the x-axis. Since you know the charge, and the electric field it's in, you know the acceleration
    (use F=qE and F=ma). Since you know the acceleration (and it's constant) use some kinematical relations and solve the problem.
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