-In a hydrogen atom, the electric force is the centripetal force. Determine the speed of an electron in orbit around a proton if the distance between them is 5.29 x 10^-11m. The mass of an electron is 9.11 x 10^-31.
-A charge with a value of 2.2 x 10^-6C is placed 12cm to the left of a 3.8 x 10-6C charge. At what point between the charges should a test charge be placed so it experiences no net elastic force?
-Determine the magnitude of the electric field 0.75m from a 0.63 C master charge. What would be the force on a 0.50C test charge placed here?
-A drop of oil is floating between two parallel plates with a separation of 8.3mm. If the mass of the oil drop is 2.7 x 10^-15 kg and it's charge is -9.612 x 10^-19 C, determine the voltage across the charged plates and determine which plate is positive.