I'm new in this forum, so i don't know if this is in the correct place..(adsbygoogle = window.adsbygoogle || []).push({});

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

I got 3 charges

q1= 2.0x10^-6C

q2=8.0x10^-6C

Q=4.0x10^-6C

They're placed in the corners of a triangle like in this draw

I have to know the force that q1 and q2 act on Q, the magnitude, and the direction

2. Relevant equations

F=(kq1q2)/r^{2}

for the angle which is 38.65 i do the tan^{-1}of .40/.50

3. The attempt at a solution

Fq1Q=( (9x10^{9}Nm^{2}/c^{2}) (2.0x10^{-6}C) (4.0x10^{-6}C))/(.50m)^{2}

Fq1Q= .288N

So know i split in the components of X and Y right?

x= .288(cos38.65) Y= .288 (sin38.65)

x=.22N Y= .1798

Fq2Q=( (9x10^{9}Nm^{2}/c^{2}) (8.0x10^{-6}C) (4.0x10^{-6}C))/(.50m)^{2}

Fq2Q= 1.152N

x=1.152 (cos 38.65) Y=1.152 (sin38.65)

x=.8999n y=.7119n

Now for the magnitude

x= .22+.899=1.119N

y=-.1798+.7119= .5321N

sqrt((1.119)^{2}(.5321)^{2})= 1.311N

as for the direction

tan^{-1}= (.5321/1.119)= 25.43°

so.. am I right?

all sugetionts are really apreciated, tips and stuff.. hope anyone can help me

sry if my descriptions are wrong, I'm from mexico and my english is not perfect:shy:

if someone also could give me other exercises for practice... it will be perfect!

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# Homework Help: Coulombs law problems

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