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

An electron with speed 2.0E7 m/s is traveling parallel to a uniform electric field of magnitude 1.18E4 N/C. How far will the electron travel before it stops? How much time will elapse before it returns to its starting point

q = 1.60E-19 C

mass of electron = 9.11E-31 kg

velocity (initial) = 2.10E7 m/s

velocity(final) = 0 (zero)

2. Relevant equations

Electric Field

E=F/q --> F=qE

Acceleration / Force equation

a=F/m

Constant Acceleration

v(final)^2=v(initial)^2 +2a*(delta x) --> delta x = (v(final)^2 - v(initial)^2) / 2a

3. The attempt at a solution

F=qE = (1.60E-19 C)(1.8E4 N/C) = 2.88E-15N

a=F/m = (2.88E-15N) / (9.11E-31 kg) = 3.16E15 m/s^2

delta x = (v(final)^2 - v(initial)^2) / 2a

delta x = (0 - 2.10E7 m/s) / 2*(3.16E15 m/s^2)

delta x = -6.97785E-2 m<--- ACCORDING TO MASTERING PHYSICS THIS ANSWER IS WRONG!!!

with the 2nd part of the question... I was going to use the equation

delta x = 1/2[v(initial) + v(final)]*t

but since my delta x is wrong, i haven't quite started this part.....

Any and all help will be appreciated! Thank you in advance!

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Electron traveling parallel to a Uniform Electric Field

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