Problem 41

Submitted by David S. Hall on Thursday, 11/5/2009, at 8:21 PM

Q. The question asks to find a function for F with respect to v, and I am having trouble seeing how the velocity of the bar changes the force on it. Any hints?

A. Initially there is a force on the bar because of the current it carries. Then the bar starts moving. A moving conductor in a magnetic field generates an emf, and that emf will change the current that passes through the bar; and, therefore, the force on the bar.