Electromagnetic Induction in action!

Video courtesy of: mist8k

Fig: A little simplified illustration :)

What really happens here is when the strong magnet falls through the copper or aluminium pipe, its magnetic field lines are constantly being cut by the pipe. This induces an emf, which induces eddy currents to flow around in the pipe. These eddy currents flow in a direction so as to generate a magnetic field to OPPOSE the change that is causing it, via Lenz's Law. Therefore, it is understood that the pipes must be made of non-magnetic but electrically conducting materials.

Determine the polarity of the strong magnet that is falling through. If the north pole approaches the mouth of the pipe, eddy currents will flow anti clockwise(by right hand grip rule) to induce a north pole at the mouth of the pipe to oppose the permanent magnet's fall.

The process is repeated throughout the pipe, with the eddy currents instantly adjusting their flow to always oppose the fall of the magnet, resulting in a seeming act of defiance of gravity!

#physicstuition #electromagneticinduction