Free-Response Questions
6. Four point charges, each with a magnitude |q| = 6.0 nC, are fixed at different locations along the perimeter of a square of side length d = 4.0 cm. The origin of the xy-plane is fixed at the top right corner of the square.
a. Draw and label a diagram that includes all electric field vectors at point O. Include x- and y-components if necessary.
b. Calculate the magnitude and direction of the net electric field vector (E) at point O.
c. If a charge Q = -3 μC is placed at point O, calculate the magnitude and direction of the electric force vector (F) on Q.
Bonus: Charge Q now accelerates off to an infinite distance away from the sources. If a fifth charge q' is now placed at the location r = -d(i + j), determine its charge that would create a net electric field of zero at point O.