Identical point charges Q are placed at each of the four corners of a rectangle measuring 2.35 m by 3.17 m. If Q = 35.9 μC, what is the magnitude of the electrostatic force on any one of the charges?

Question

jamesj · Answer

Choose one of the charges, top left corner for instance.  Use Coulomb's law to calculate the force on that object from each of the three objects. Make sure you write each of them as vectors, because each of the three have different directions. Add them up.  Find the magnitude.

By symmetry, the magnitude of the force on the other three charges will be equal.