A 10-cm-long thin glass rod uniformly charged to 13.0 and a 10-cm-long thin plastic rod uniformly charged to - 13.0 are placed side by side, 4.00 apart. What are the electric field strengths to at distances 1.0 cm, 2.0 cm, and 3.0 cm from the glass rod along the line connecting the midpoints of the two rods?

Question

A 10-cm-long thin glass rod uniformly charged to 13.0  and a 10-cm-long thin plastic rod uniformly charged to - 13.0  are placed side by side, 4.00  apart. What are the electric field strengths  to  at distances 1.0 cm, 2.0 cm, and 3.0 cm from the glass rod along the line connecting the midpoints of the two rods?

jamesj · Answer

The electric field will of course be the superposition of the two fields. So find the field of each rod at each point and add them. For the fields of a finite rod itself, if you don't know how to calculate them, have a look at this: http://www.phys.uri.edu/~gerhard/PHY204/tsl31.pdf