Question

1- For a uniform electric field, how is the electric potential energy similar to the gravitational potential energy in a uniform gravitational?

2-If a positive charge and a negative charge moving the same way in an electric field have the same change in electric potential energy?

3-For a positive charge moving in an electric field, which direction of motion will cause the electric potential energy to increase? Decrease? Stay constant?

4-How would the answers to the previous question be different if the charge moving is negative?

5-Where is the potential energy of two point charges zero?

6- If two positive charges are moved closer together what happens to the electric potential energy of the charges?

7-If two negative charges are moved closer together what happens to the electric potential energy of the charges?

8- If a positive charge and a negative charge are moved closer together what happens to the electric potential energy of the charges?

9-What does it mean that the electric force is conservative?

10-How is the electric potential energy of a collection of point charges determined?

11-When is the electric potential energy of an electric dipole a minimum and a maximum?

12- What is the electric potential? What is the cause of the electric potential?

13-How is the electric potential related to the electric potential energy?

14-What is the unit of the electric potential? What is an equivalent unit for the electric field?

15-How does the electric potential vary inside a parallel plate capacitor?

16-How does the electric potential vary from a point charge?

17-What are equipotential surfaces? What is a contour map?

18-What is an elevation graph?

19-If positive charge is moving from a point of higher potential to a point of lower potential what happens to speed of the charge?

20-What would happen for a negative charge?

21- If positive charge is moving from a point of lower potential to a point of higher potential what happens to speed of the charge?

22-What would happen for a negative charge?

23-How is the electric potential for a collection of charges found?

24- Describe the equipotential surfaces for a point charge, an electric dipole, and a parallel plate capacitor, If a charge is moving along an equipotential surface, is any work done on the charge by the electric field? Why or why not?

Answer 1

Following are the Answers, 1) Potential energy in uniform electric filed is, U_E = 1/4 pi epsilon_0 q_1 q_2/r Rightarrow U_E propto q_1 q_2: U_E propto 1/r and potential energy in uniform gravitational fields, U_g = G m_1 m_2/r Rightarrow U_g propto m_1 m_2: U_g propto 1/r No, the magnitude of work done on them will be same but will have opposite sign Increase in potential energy when it moves opposite to field. Decrease in potential energy when it moves in the same direction of field. Increase for same direction and decrease for opposite direction At the line perpendicular bisector to the line joining the two point charges Electric potential energy increases Electric potential energy increases Electric potential energy decreases Electric force is a conservative force which means that the work done by the electric force in closed route is always zero. The electric potential energy of the pair of charges are algebraically added with each other.