A negatively charged plastic rod comes close to but does not touch a neutral metal sphere. While the rod is still close, someone momentarily touches the opposite side of the sphere with her finger. The charge on the metal sphere is a) negative. c) neutral. b) positive d) cannot be determined.

2. In the figure below, two charges spheres have equal masses of 2.56 grams. x = 2.5 cm, L = 13 cm, and D = 22 cm. D Use the information provided to calculate the angle each string makes with the vertical, the tension in each string, and the magnitude of the charge on each sphere. In the figure above, the charges repel each other. They are both positive or both negative. Historically, how did Benjamin Franklin decide what charge was positive? (Use Google's help as needed.)

An electroscope is charged by touching it with a positive glass rod. The electroscope leaves spread apart and the glass rod is removed. Then a negatively charged plastic rod is brought close to the top of the electroscope, but it doesn’t touch. What happens to the leaves?A. The leaves move closer together.B. The leaves spread farther apart.C. The leaves do not change their position.

5.) Two equally and oppositely charged plates are separated by a distance. The top plate is positively charged. Which of the following statements is correct? A.) A positive charge will gain potential energy as it moves away from the top plate. B.) A negative charge will gain kinetic energy as it moves away from the top plate. C.) A positive charge will gain kinetic energy as it moves away from the bottom plate. D.) A negative charge will gain potential energy as it moves away from the top plate. E.) Positive and negative charges will not react to movement between the plates. 6.) Four charges are placed at the corners of a square whose side length is L. What is the direction of the electric field at the center of the square? +Q -Q