Which way is V in electromagnetic induction?

giladsof · Jun 5, 2011

Text problem about a conducting rod sliding on two conducting tracks over a hill-and-valley track with points A, B, C, D, in a downward magnetic field, followed by a handwritten-style student working with arrows for force and current.

ideasrule · Jun 5, 2011

You're trying to calculate the current induced by the movement of the rod. That current is 0 when the rod is at equilibrium, because the rod wouldn't be moving. Even when it's not at equilibrium, the induced current is usually so small as to be negligible compared to the current supplied by the power source.

So you just need to consider the force applied by the magnetic field on the rod, due to the existing current I. There's no need to consider induction.

giladsof · Jun 5, 2011

OK... As I try your idea I get into the following dilemma: which way is V? The movement of the rod or the movement of the current?

Unfortunately neither one of those options creates a force upwards using the right hand rule... \:

Two diagrams of a wire loop on a curved track with points A, B, C and D, each showing a magnetic field into the page (circled crosses), velocity arrows, force arrows and downward B arrows, for two cases: V along the rod, and V along the current.

Which way is V in electromagnetic induction?

Discussion

Similar threads