A small sphere of mass m = 7.50 g and charge q1 = 32.0 nC is attached to the end of a string and

Question

hangs vertically as in Figure 2. 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 as in Figure 2.
(a) Find the tension in the string.
Answer: 0.115 N
(b) If the string can withstand a maximum tension of 0.180 N, what is the smallest value d can have
before the string breaks?
Answer: 1.25 c