A point charge +5μC is fixed at the origin. Point P is on the x-axis at 0.40m, and point Q is on the x-axis at 0.20m. Use k=9×109N m2C−2.
a. (i) Find the potential difference VQ−VP due to the source charge.
b. (ii) Calculate the work done by an external agent in moving (a) a +1μC charge, (b) a −1μC charge from P to Q.
c. (iii) Is the work obtained in part (ii) dependent on the path taken between P and Q? Give a brief reason.