and its direction, given by the cross-product J B, opposes the direction of v. This has the effect of damping the movement of
the plate into the gap. If the conductivity σ of the plate were infinite, the plate would be repelled from the gap. In reality, σ is
finite and the plate is decelerated as the power due to induced currents is dissipated in the plate. The plate penetrates into the
gap, decelerating, and, eventually, reaches a state of static equilibrium at the lowest point of its oscillation. In the case this does
not happen immediately; the plate may continue to oscillate in a highly damped motion until the pendulum has completely
stopped. This principle is used extensively on locomotives and trucks. Conducting disks are installed on the axles of the vehicle
and electromagnets are placed around them such that the disks move in the gap of the electromagnets, as in Figure 10.22.