1. A 7.73 nC charge is located 1.87 m from a 3.86 nC point charge. Find the magnitude of the electrostatic force in one charge exertson the other. Is the force attractive or repulsive?
2. A small sphere of mass m= 7.60 g and a charge q1 = 29.9 nC is attracted to the end of a string and hangs vertically as in the figure. A second charge of equal mass and charge q2 = -58.0 nC is located below the first charge a distance d = 2.00 cm below the first charge. Find the tension in the string. If the string can withstand a maximum tension of 0.180 N, what is the smallest value d can have before the string breaks?