a point charge q=5.0 micro coulombs is placed at each corner of an equilateral triangle with sides .26 m in length.

a. what is the magnitude of the electric field at the midpoint of any of the three sides of the triangle?

2 answers

Well, the E component due to the two nearest charges is equal an opposite, so the result E from those two charges is zero. The last charge contributes the resultant E. So figure the distance, and E then is q/r directed away from that opposite charge.
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