A pendulum with a metal sheet or comb-shaped bob is swung through the poles of a large electromagnet. As the metal moves through the magnetic field, eddy currents are induced in the sheet. These currents generate their own magnetic fields that oppose the motion of the pendulum, creating a damping force. The solid metal bob experiences significant damping, while the comb-shaped bob experiences less damping, illustrating the effect of eddy currents and their role in magnetic braking.