posted by anna .
A small sphere of mass m = 6.40 g and charge q1 = 30.3 nC is attached 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 as in the figure.
(a) Find the tension in the string.
(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?