Emf induced on an eccentric rotating bar

1. Nov 7, 2011

Termotanque

Suppose that a conducting bar is rotating with a speed ω, around an axis a distance a from one end, and b from the other. Suppose further that it is immersed in a uniform magnetic field B parallel to the axis of rotation, and that the measured difference of potential between both ends is V. I want to calculate the appropriate B.

I tried calculating an infinitesimal potential difference dV appearing when an infinitesimal slice of the bar of length dr is rotating, such that the electric and magnetic force cancel: dV = ωrB dr, and then integrating this from -a to +b. This approach appears to be incorrect.

Any hints will be appreciated.