Hey, just did a 25 question multiple choice paper and this was the only one that I got wrong. Was hoping someone could enlighten me.

I got the force acting on the conductor:Originally Posted byAQA PHYA4/1 Jan 2010

So figured since that is the force on the entire conductor, then the force on one electron would be the force divided by the number of electrons:

But the answer is

I know I am neglecting the cross-sectional area but not sure where it would come in.

Thanks.