Basic Force Concepts Homework: Electron Held Stationairy in Electric Field

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Homework Statement


An an electric field.
An electron is held stationairy in a vacuum between two charges metal plates.
It is attracted to the positive plate since unlike charges attract. The weight of the electron balannces the electric force.

Now these two forces are balanced. Acceleration is 0 ms^-2
That would also mean the electron is moving with constant velocity. But if that's true, how could the electron be held stationairy?
 
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fffff said:
Now these two forces are balanced. Acceleration is 0 ms^-2
That would also mean the electron is moving with constant velocity. But if that's true, how could the electron be held stationairy?
You've made an erroneous leap there. Zero acceleration does not imply non-zero velocity. Consider yourself sat in your chair in front of your computer. Are you accelerating? Do you have a non-zero velocity?

Edit: Okay, Doc Al put it simpler than me :blushing:
 
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fffff said:
That would also mean the electron is moving with constant velocity. But if that's true, how could the electron be held stationairy?
Not moving is a perfectly fine example of constant velocity! :wink: (The velocity is zero.)