(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A uniform electric field exists in a region between two oppositely charged plates. An electron is released from rest at the surface of the negatively charged plate and strikes the surface of the opposite plate, 2.6 cm away, in a time 3.8 x 10-8 s. (a) What is the speed of the electron as it strikes the second plate? (b) What is the magnitude of the electric field?

2. Relevant equations

F = q E

E = F/ q = q/4pi[tex]\epsilon[/tex] r^2

V[tex]_{F}[/tex]^2 = V[tex]_{0}[/tex]^2 + 2a( x - x[tex]_{0}[/tex])

F = ma

3. The attempt at a solution

I thought finding the speed was obvious

i just converted the cm into meters and divided by the time

it came out to about 6.8e5

...which was wrong

I know how to relate the E field equations to speed and acceleration

and this was my final simplified eqation without pluging in the numbers

E = (V^2)m / (2 q x)

q was the charge of an electron

x was 0.026 meters

V was the 6.8e5

m was the mass of an electron

is the velocity the only thing holding me back from the right answer?

or is there something else that's wrong?

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# Homework Help: What is the speed of the electron as it strikes the second plate?

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