Why is the direction of the current shown in each part of Figure 24.6 opposite to the electric field produced by the wire’s charge separation?
Step 1 of 2
The direction of current is either that in which the positive charge flows or opposite to that in which the negative charge flows. And the direction of an electric field is always from the positive charge toward the negative charge.
The directions of current as well as electric field are clearly shown in part (a) of the figure. The reason why they are opposite to each other is simple. The flow of current is caused by the generator. Since the current is flowing upward at that particular instant, it is causing the positive charge to flow in its own direction while the negative charge to flow opposite to its direction which is obvious.