Four charges are located at the four corners of a square of side b:

Question

Q1 = 3 nC at the top right corner,
Q2 = -4 nC at the bottom right corner,
Q3 = 5 nC at the top left corner,
Q4 = 7 nC at the bottom left corner.

What is the electric field at the midpoint between Q3 and Q4?

Answer 1

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four point charges field at midpoint

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