* Experimental purpose: Observe the phenomenon of the pendulum swinging back and forth between the two magnetic poles of the magnet, and analyze the cause of this phenomenon. * Overview: The electromagnetic damping demonstrator is suitable for the mathematics of the electromagnetic induction part of high school physics. Use the pendulum in the demonstrator to reciprocate between the two magnetic poles of the magnet to observe the electromagnetic damping effect. * Experimental equipment: metal pendulum, magnet. * Experimental principle: A single pendulum made of a metal plate. When the pendulum reciprocates between the two magnetic poles of the magnet during the swing process, the magnetic flux changes in a certain local area of the pendulum, thus generating an induced electromotive force. In turn, an induction power source is generated, which is the eddy current. * According to Lenz's law, the action of the magnetic field of the eddy current and the original magnetic field hinders the movement of the pendulum. Therefore, the metal pendulum is always subjected to a damping force, just like swinging in a certain viscous medium, and stops quickly In the future, this damping originated from electromagnetic induction, so it is called electromagnetic damping.