Hey I'm a new time member but I hope to use this forum for my college Physics 2 class, anyways:(adsbygoogle = window.adsbygoogle || []).push({});

1. Question: Two charges are D = 2.5 m apart and lie on the x-axis. What must be the magnitude of the charge on the right one, Q2, (in C) so that the electric field is zero at x = 1.75 meters. Let Q1 be at the origin and have a charge 17 C.

2. Equations I'm using.

E(total)=E1+E2...

E=k*q/r^2

3. My attempt:

E1=(8.99E9)(17C) / (1.75^2) = 4.990E10

E2= k*Q / (1.75^2)

E(total) = E1 + E2

0 = E1+E2

-E1=E2

Q= (-4.990E10)(1.75^2) / (8.99E9)

Q= -16.9987

I've just learned electrical fields / coulombs law, for a problem like this I just need some explanation on what I'm doing wrong. I thing what the biggest problem is and confusing this is it initially is 2.5m apart but they want you to find it at 1.75m, I'm going to keep working but I feel like the 2.5 is relevant and I'm not using it. Thanks in advance.

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# Homework Help: Physics 2 Electric Fields

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