Goal: Hone the vector nature of the electric field
Four charges are positioned as
shown. What is the direction of the electrical field at the origin?
- Along i or in the +x direction
- Along -i or in the -x direction
- Along j or in the +y direction
- Along -j or in the -y direction
- Along some other direction
- E=0 at the origin
(6) Difficulty with this question usually indicates that students are
not familiar with vectors. Good follow up question: ask whether it
matters if the charges are along a 45 degree line.