What is the Velocity of Electrons between Charged Plates?

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Punch
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Homework Statement



A beam of electrons, with kinetic energy of 500eV, enters mid-way into the space between two oppositely charged parallel plates with a potential difference of 100V

Homework Equations



Determine the velocity of the electrons

The Attempt at a Solution



KE=0.5mv^2
500(1.60x10^-19)=0.5(500 x 9.11 x 10^-31)(v^2)
v=5.93x10^5
 
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First, this isn't really advanced physics, this should be in the introductory physics section.

Second, I have no idea what you did with your equation work. Why is there a 500 term in the mass for the electron? There is only 1 electron, in the beam there may be multiple electrons, but each one carries the same energy.

Also, determine the velocity WHERE? It will be different at different points throughout the apparatus.
 
Last edited:
Punch said:
KE=0.5mv^2
500(1.60x10^-19)=0.5(500 x 9.11 x 10^-31)(v^2)
v=5.93x10^5

what is that 500 doing there?

you have just found initial velocity (though it has a small error as i said above)

you also need to calculate the new velocity perpendicular to plates ... which depends on how far electrons have moved b/w the plates.