0.1 A student is performing an experiment with two identical small metal balls, A and B. Initially, ball A contains 6.0-μC net charge with an unknown sign and ball B is neutral. The student brings them in contact and then separates them by 20 cm. Both balls remain isolated. (a) Is the electric force between A and B attractive, repulsive, or zero? (b) What is the magnitude of the electric force between the balls? [Answer: 2.025 N] 0.2 Two small objects, A and B, are initially neutral. A student managed to transfer 2.0 mC electrons from A to B. They are then separated by 50 cm and remain isolated. (a) Is object A positively or negatively charged? (b) Is object B positively or negatively charged? (c) Is the electric force between A and B attractive, repulsive, or zero? (d) What is the magnitude of the electric force between A and B? [Answer: 1.44 x 105 N]