2.1. Four 10nC positive charges are located in the z = 0 plane at the corners of a square 8cm on a side. A fifth 10nC positive charge is located at a point 8cm distant from the other charges. Calculate the magnitude of the total force on this fifth charge fore = €0: Arrange the charges in the xy plane at locations (4.,4). (4,-4), (-4.4), and (-4,-4). Then the fifth charge will be on the z axis at location z = 4/2, which puts it at 8cm distance from the other four. By symmetry, the force on the fifth charge will be z-directed, and will be four times the z component of force produced by each of the four other charges.

2.1. Four 10nC positive charges are located in the z = 0 plane at the corners of a square 8cm on a side. A fifth 10nC positive charge is located at a point 8cm distant from the other charges. Calculate the magnitude of the total force on this fifth charge fore = €0: Arrange the charges in the xy plane at locations (4.,4). (4,-4), (-4.4), and (-4,-4). Then the fifth charge will be on the z axis at location z = 4/2, which puts it at 8cm distance from the other four. By symmetry, the force on the fifth charge will be z-directed, and will be four times the z component of force produced by each of the four other charges.