A2L Item 116
- Description: Indicate the direction of the total electric field at the origin due to two rods.
- Goal: Hone vector nature of electric fields
- Source: UMPERG-em97Q
- Keywords: Distributed Charges, Electric Field, Electromagnetism
The question for students:
Two uniformly charged rods are positioned horizontally as shown. The top rod is positively charged and the bottom rod is negatively charged. The total electric field at the origin
- Is 0.
- Has both an x and a y component.
- Points totally in the i direction.
- Points totally in the -i direction.
- Points totally in the j direction.
- Points totally in the -j direction.
Commentary for teachers:
Answer
(6) Along the y-axis, by symmetry, the electric field due to either rod points along the y-axis. At the origin the contribution to each rod is the same and points down.