posted by ChEm .
A rod 14.0 cm long is uniformly charged and has a total charge of -22.0 μC. Determine the magnitude
and direction of the electric field along the axis of the rod at a point 36.0 cm from its center.
ans:E = 1.59e6 N/C, pointing to the left
I don't know what I should use for L and a, and I've tried every combination possible and I still can't get it.