How do electrical charges attract/repel each other

AI Thread Summary
Electrical charges exhibit attraction and repulsion based on their polarity, with like charges repelling and opposite charges attracting. In the given scenario, charge C is influenced by both charge A and charge B, which are both positive and thus repel charge C. To determine the resultant vector on charge C, one must consider the directions of the forces exerted by charges A and B on it, rather than the forces charge C exerts on them. Charge C will experience forces pulling it leftward and slightly downward due to the repulsion from charges A and B. Understanding these directional forces clarifies the resultant vector's direction for charge C.
DrKARMA
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Ok. I understand like repel and opposite attract. There are these physics homework with 3 charges and find the force from 2 of them on one. I understand the math: the only problem is my signs are wrong due to not understanding the direction of the force.

For example,
There's a positive charge (A) on origin. There's a positive charge (B) 4 meters up. There's a neg charge (C) 3 meters x-axis and 4 meters y axis. Find the resultant vector on charge 3?

For me, I would make charge 3 my main object. It would then attract and pull Charge B, making a vector to the SOutheast. It would then pull charge A to the NE direction. Then the resultant vector would be to right. But I am wrong.


I am literally confused. I do not know which direction to draw the vectors pointing. Please help. Thank you in advance.
 
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If you're trying to find the vector of charge C, then you need to find out which direction the other 2 charges are pulling on it, not which way charge C is pulling the other two.
 
So the resultant is to the left?
 
DrKARMA said:
So the resultant is to the left?

If opposite charges attract, then charge C is attracted towards charge B, correct?
And it also is attracted towards charge A.
Since both A and B are to the left of C, I'd say that is correct. It should have a vector left and a little down.
 
Alright thanks. I think I get it now
 
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