Four point charges are located at corners of a square with sides length a. They are arranged (+q,-q,+q,-q) with +Q in the middle. What is the magnitude and direction of the net force.

I would guess that the force is 4kqQ/(a^/2) but someone is saying its 4Fsin45 can someone explain that part and I know it's goin g downward but is there a way to mathematically show that?

Question

Four point charges are located at corners of a square with sides length a. They are arranged (+q,-q,+q,-q) with +Q in the middle. What is the magnitude and direction of the net force. 

I would guess that the force is 4kqQ/(a^/2) but someone is saying its 4Fsin45 can someone explain that part and I know it's goin g downward but is there a way to mathematically show that?

anonymous · Answer

Have you drawn a picture of this? The negative charges cause forces that point toward the charge Q, from opposite sides. The positive charges cause forces that point away from Q, from opposite sides. If you rotate your square so it looks like a diamond, then draw your x,y axis, you can see that the net force will be zero.

anonymous · Answer

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