Find the electric field at a point midway between two charges of +39.5 ✕ 10-9 C and +72.0 ✕ 10-9 C separated by a distance of 31.8 cm.

2 answers

E = kq/r^2 where r is 1/2 .318m. Sum the effect of each vectorially. (note they're pushing in opposite directions.
l