Electron Speed in a Voltage Gradient

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The discussion focuses on calculating the speed of an electron in a 15kV voltage gradient. It confirms that the initial kinetic energy is zero and the final potential energy is also zero, allowing the use of the equation Ui + Ki = Uf + Kf. The kinetic energy of the electron just before hitting the cathode can be expressed as Kf = q * V, where q is the charge of the electron. Participants agree that this approach is valid for determining the electron's speed. The conversation concludes with a positive affirmation of the solution's validity.
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Homework Statement



The voltage between two plates is 15kV. If an electron's speed is zero as it leaves the anode, what is its speed just before it hits the cathode?

Homework Equations



U=q*V



The Attempt at a Solution



I guess my question is can I use the equation Ui + Ki = Uf + Kf and since there is no initial kinetic anergy and no final potential energy can I substitute Kf of the electron in for the U in the equation U=q*V? Would q be the charge of the electron?
 
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Yes you can do what you suggested, Kf=q*V and you can find the speed from Kf. And yes q is the charge of the electron.

Hope it helps,
 
yes thanks
 

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