1. Q Q P a Two equal positive charges Q are located at the base of an equilateral triangle with sides of length a. What is the potential at point P (see diagram)? “No way you are going to give us a test problem this easy!” Are you going to complain if we do? What would you do differently if you were told Q is negative?

2. An electron is released from rest at point P. What path will the electron follow? What will its speed be when it passes closest to either charge Q? Q Q P a -

3. Q Q a - - v v i =0 initial final a/2 Don’t mix up your big V’s and little v’s! 0 0

4. An electron is released from rest at point P. What path will the electron follow? What will its speed be when it passes closest to either charge Q? Q Q a - - v v i =0 initial final a/2

5. Three equal positive charges Q are located at the corners of an equilateral triangle with sides of length a. What is the potential energy of the charge located at point P (see diagram)? What would happen if the charges were held at rest in the above configuration, and then released? Q Q P a Q a =Q 1 =Q 3 Q2=Q2= What would be different if you were asked for the potential energy of the system of three charges?