# Velocity of electrons

## 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

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.

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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.