1. You rub a rod made out of rubber with a piece of fur so that the rubber rod becomes negatively charged. What happened? You are given 4 possible answers. Choose the correct answer. Explain why this is the correct answer and also explain why each of the other answers is wrong.
A. Protons are removed from the rod.
B. Electrons are added to the rod.
C. The fur becomes negatively charged also.
D. The fur remains neutral.
2. Charge A and charge B are 1.00 m apart. Charge A is +2.00 C and charge B is +3.00 C. Where do I have to locate a charge C so that the force on charge C is zero? Choose the correct answer. Explain why this is the correct answer and also explain why each of the other answers is wrong.
A) to the left of charge A or to the right of charge B
B) in the center between A and B
C) between A and B, but closer to A
D) between A and B, but closer to B
3. Two charges, +Q and -Q, are located two meters apart and there is a point along the line that is equidistant from the two charges as indicated by the black dot in the figure. Which vector best represents the direction of the electric field at that point? Explain your answer. You can draw other vectors to illustrate your explanation.
4. A dipole is placed in a uniform electric field as shown in the figure. What happens to the dipole? Is there linear motion? Justify your answer and also indicate the direction of motion. Is there rotational motion? Justify your answer and also indicate the direction of motion. If there is motion, will it continue, or will the motion stop? When will it stop?
