A large positively-charged object with charge q = 3.75 ?C is brought near a negatively-charged plastic ball suspended from a string of negligible mass. The suspended ball has a charge of q- = -53.3 nC and a mass of 15.5 grams. What is the angle the string makes with the vertical when the positively charged object is 19.5 cm from the suspended ball? The positively-charged object is at the same height as the suspended ball.