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

A charge of -12.0nC is placed on the y-axis at y = -15cm and a charge of +12.0 nC is placed on the y-axis at y = 15cm. Determine (a) the electric field of each charge separately at x = 20.0cm, and (b) the net electric field due to these charges at x = 20.0 cm. (c) What force would act on an electron when it passes through this point on the x-axis moving at 1.73E6 m/s?

2. Relevant equations

E=k|Q|/r^{2}

F=qE

c^{2}=sqrt(a^{2}+b^{2})

3. The attempt at a solution

(a) E=k|Q|/r^{2}= [(8.99E9 Nm^{2}/C^{2}) |12E-9C|] / (0.25m)^{2}= 1726 N/C

So....

E (due to +12 nC) = (1726 N/C , 323 degrees)

E (due to -12 nC) = (1726 N/C , 217 degrees)

(b) E_{NET}= 2*(1726 N/C)*cos(53 degrees) = 2077 N/C, 270 degrees

(c)my problem is this part

I am given v = 1.73E6 m/s but with F=qE_{NET}, velocity of the electron is irrelevant? or may be I'm wrong.

F=qE_{NET}=(1.60E-19 Nm^{2}/C^{2})(2077 N/C ,270degrees)

According to the answer key, the direction of the Force is 90 degrees? Why? From my drawing attached, I'm seeing 270 degrees. What am I doing wrong?

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: Electric Force acting on an electron

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