A 21.84. Two tiny balls of mass Figure 21.46 Problem 21.84. m carry equal but opposite charges of magnitude q. They are tied to the same ceiling hook by light strings of length L. When a horizontal uni- L L form electric field E is turned on, the balls hang with an angle between the strings (Fig. 21.46). (a) Which ball E (the right or the left) is posi- tive, and which is negative? (b) Find the angle 8 between the strings in terms of E, 9, m, and g. (c) As the electric field is gradually increased in strength, what does your result from part (b) give for the largest possible angle o