the magnetic field of a cylindrical magnet that has a pole-face diameter of 3.3 cm can be varied sinusoidally between 29.6 t and 30.0 t at a frequency of 13 hz. (the current in a wire wrapped around a permanent magnet is varied to give this variation in the net field.) at a radial distance of 1.9 cm, what is the amplitude of the electric field induced by the variation?