Charge 1 is located along the x axis and has a magnitude of +1.6E-6C and Charge 2 is located 1m away from charge 1 with a magnitude of -4.8E-6C. A third point charge of magnitude Q is brought from far apart and placed on the line joining the two charges and at a point where the charge q experiences no net force at all. What is the distance of that point from the origin and what should be the sign of this unknown charge q?(adsbygoogle = window.adsbygoogle || []).push({});

This is what I came up with so far...

F1 = K (Q1)(Q2)/X^2

F2 = K (Q2)(Q3)/(1m-x)^2

You set them equal to eachother and get

K(Q1)(Q2)/X^2 = K(Q2)(Q3)/(1.00-x)^2

Cancel out K and Q3 leaving;

(1.00-x^2)/X^2 = (Q2)/(Q1)

1.00-x/x = square root (4.8E-6C/1.6E-6C)

1.00-1x = 1.73x

1.00=1.73x +1x

1.00=2.73x

x = .366

Does anybody know if this is correct?

Also I do not know how to figure out what the sign of this charge should be so if anybody could help me I would appreciate it!

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# Homework Help: Point Charges

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