Homework #2

Due 10/5/00

(1) Cheng Problem 3.17

(2) Cheng Problem 3.18

(3) Cheng Problem 3.19

(4) Cheng Problem 3.20

(5) One type of quadrupole is an arrangement of 4 charges of magnitudes +q. -q, +q, -q arranged at the corners of a square. The spacing of the charges is negligible compared to the distance to an observation point where the field is measured. Calculate the potential distribution from a quadrupole and thereby the various field components. Plot the equipotential surfaces in the plane of the quadrupole, and in a plane perpendicular to the plane of the quadrupole passsing through the center of the square where the charges are located. Plot the radial electric field variation in the plane of the quadrupole.

(6) Repeat (5) for a linear quadrupole, where the charges are +q, -2q, +q arranged in a straight line.