1. A positive electric charge is put on a styrofoam sheet by rubbing one side of it with fur. Which of the following best represents the final charge distribution? Fur

2. A styrofoam chip that is charged positively is attracted to a plastic rod is brought close. Styrofoam The plastic rod is (a) negatively charged (b) positively charged (c) neutral (uncharged) (d) a or c (e) Not enough information to tell.

3. Two positive point charges separated by a distance r experience a force F between them. They are then moved so they are separated by r/2. The force between them is now equal to (a) F/2 (b) 2F (c) 4F (d) F/4 The force between them is (a) attractive (b) repulsive (c) not enough information to tell

4. For the charges below which diagram best shows the forces on charge C?

5. For the charges below, which expression best gives the total force on charge C? (a) F = F A + F B (F = magnitude if no vector sign) (b) F x = F Ax + F Bx, F y = F Ay + F By (c) (d) b & c (e) a, b & c

6. A positive charge A is shown below. + P A What is the direction of the electric field at point P? (a) (b) (c) Not enough information to tell.

7. For the charges below, which vector diagram best represents the total electric field at charge B?