(20 pts.) A small sphere with mass 1.20 g hangs by a thread between two very large parallel vertical plates 5.00 cm apart as shown in the gure. The plates are insulating and have uniform surface charge densities +0 and or. The charge on the sphere is q = 9.80 x 10'6 C. What potential difference between the plates will cause the thread to make an angle of 30.0 with respect to the vertical? ' 30.0 5.00 cm