The magnitude of the magnetic field in a magnetic resonance imaging (MRI) machine can be as great as \(B=3.0 \mathrm{~T}\). Under normal circumstances, this field cannot be shut off by just flipping a switch. Instead the magnitude needs to be carefully decreased to zero. In an emergency, however, the magnet can be "quenched" so that \(B\) reduces to zero in \(20 \mathrm{~s}\). Such a quench can cost thousands of dollars and likely damages the magnets. Assume that the magnetic field exists inside a cylinder of radius \(R=300 \mathrm{~mm}\) and length \(\ell=200 \mathrm{~mm}\). How much magnetic potential energy is dissipated when the magnetic field is quenched in this way, and what is the average rate at which energy is dissipated?