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Homework Help: Electric field

  1. Jan 27, 2006 #1
    I need help with this question if anyone can give me an idea of what to do. Any help would be greatly appreciated.

    An electron is released from rest in a uniform electric field. The electron accelerates vertically upward, traveling 4.50 m in the first 3.00 micro seconds after it is released.
    What is the magnitude of the electric field?
    Last edited: Jan 27, 2006
  2. jcsd
  3. Jan 27, 2006 #2
    Do you know what force is in charge of accelerating the electron?
  4. Jan 27, 2006 #3
    yes it is F=E * q

    I know that q = 1.62 * 10^-19, but I still have an unknown variable.
    Last edited: Jan 27, 2006
  5. Jan 27, 2006 #4
    You can solve the acceleration using elementary kinematics. Then you'd need to relate that force to the acceleration you solved for.
  6. Jan 27, 2006 #5
    yes i know, you use y = 1/2at^2, but you still get unknown variables
  7. Jan 27, 2006 #6
    You know everything besides E. The electron's mass is standard tabulated stuff.
  8. Jan 27, 2006 #7
    Is the mass 9.10938188(72) * 10 ^-31?
  9. Jan 27, 2006 #8
    yeah that's it. it's all algebra from here on.
  10. Jan 27, 2006 #9
    Thank you so much!!!
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