A2L Item 256

Goal: Hone the vector nature of the electric field

Source: CTQ283-6

Four charges are positioned as
shown. What is the direction of the electrical field at the origin?

  1. Along i or in the +x direction
  2. Along -i or in the -x direction
  3. Along j or in the +y direction
  4. Along -j or in the -y direction
  5. Along some other direction
  6. 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.