3 electrons q1, q2, q3 setup in a right angled triangle(adsbygoogle = window.adsbygoogle || []).push({});

q1

|\

| \

q3-q2

charges are

q1 = +2.5 X 10^-17C

q2 = +3.0 X 10^-17C

q3 = +3.5 X 10^-17C

distances between the charges

q1-q3 = .03 m

q1-q2 = .05 m

setup FBD

\

\ 2F1

\

/

/ 3F1

q1

2F1 = k*q1*q2 / .05^2

= 2.7 X 10^-21N

3F1 = k*q3*q1 / .03^2

= 8.75 X 10^-21N

now I think I use cosine law to figure this out

Fnet = sqrt(2F1^2 + 3F1^2 - 2(2F1)(3F1)cos135)

= 7.1 X 10^-21

with all charges being positive, all qs are experiencing repulsion so the direction is away from q1

the question "calculate the magnitude and direction of force on q1"

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# Homework Help: Electron vector analysis question

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