a) An oil droplet with a mass of 7.20 x 10^-16 kg is moving upward at a constant speed of 2.0 m/s between two horizontal charged plates. If the electric field strength between the plates is 2.20 x 10^4 V/m, what is the charge on the oil droplet? Express your answer in the format of a.bc x 10^-de C.
b) In a Millikan-type experiment, two horizontal charged plates are 2.5 cm apart. A latex sphere of 1.3 x 10^-15 kg remains stationary between the plates when the potential difference between the plates is 400 V, with the upper plate charged positive. What is the charge on the sphere? Express your answer in the format of a.bc x 10^-de C.
c) Two large, horizontal charged plates are separated by 0.050 m. A small plastic sphere is suspended between them and is experiencing a force of 4.5 x 10^-15 N. What is the potential difference between the plates? Express your answer in the format of a.bc x 10^-c m/s.