A student is experimenting with a bicycle wheel. He turns the bicycle upside down and spins the wheel in a vertical plane at a constant rate. The diagram shows the wheel. At the place where the experiment is performed, the Earth‟s magnetic field is in a horizontal direction. It acts into and perpendicular to the paper.
A constant e.m.f. is induced across the length of each spoke.
(i) Label the hub and rim either plus or minus to show the polarity of the e.m.f.
The figure shows a wheel with the direction of motion clockwise. The hub is the center and the rim are the outerpart
The Attempt at a Solution
Well, in this problem, it is said that the magnetic field lines point inside the paper. So if this is cut, it tries to oppose it... Hence, magnetic field lines should be outside. We should use flemings right hand rule but i have no idea about what would be the new direction of the spokes of the wheel (i.e the motion) and indeed upon that i don't know the direction of E.M.F..... I need help urgently.. Thanks!