Electric Field Question: Calculating Electron Speed and Ignoring Gravity

AI Thread Summary
An electron with a mass of 9.11 x 10^-31 kg is accelerated in a uniform electric field of 1.85 x 10^4 N/C between two plates separated by 1.20 cm. To find the speed of the electron as it exits through a hole in the positive plate, the potential difference (V = ED) must be calculated, and energy conservation principles apply. The calculated speed of the electron is approximately 8,846,517 m/s, which is a reasonable estimate given the parameters. Additionally, the gravitational force acting on the electron is negligible compared to the electric force, justifying its exclusion from calculations. Resources like HyperPhysics can provide further assistance in understanding these concepts.
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Please help me with the following question:

An electron (mass m = 9.11 X 10^-31 kg) is accelerated in the uniform field E (E = 1.85 X 10^4 N/C) between two parallel charged plates. The separation of the plates is 1.20cm. The electron is accelerated from rest near the negative plate and passes through a tiny hole in the positive plate. (a) With what speed does it leave the hole? (b) Show that the gravitational force can be ignored.

I would also REALLY appreciate it if someone could direct me to a site that teaches this particular part of physics. I usually check things like this that I don't understand on www.physicsclassroom.com, but they don't teach this particular area.
 
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HINT: Calculate the potential difference between the two plates and recognize that energy is conserved! :-)
 
Tide said:
HINT: Calculate the potential difference between the two plates and recognize that energy is conserved! :-)
Which formula do I use for this?
 
The equation is: V = ED
 
After reading around a bit more, I think I figured it out.

This is the answer I got 8,846,517 m/s. Is that even close to right?
 
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