See this video:
http://www.youtube.com/watch?v=xUxGqG8u-ME
The guy moves a ring magnet on the side of a coil and can light an LED.
Is Lenz Law acting here? If yes, it's stronger or weaker than in a typical rotating dynamo?
Quote from: Rapadura on February 23, 2010, 09:57:52 PM
See this video:
http://www.A.com/watch?v=xUxGqG8u-ME
The guy moves a ring magnet on the side of a coil and can light an LED.
Is Lenz Law acting here? If yes, it's stronger or weaker than in a typical rotating dynamo?
Yes, Lenz acts here too.
Because a LED is basically a diode, the induced current can only flow in one direction only, hence its loading effect is ON for every second half wave of the induced AC waveform (either positive or negative, depends on the diode connection) and not ON for a full wave like in case of an incandescent light bulb for instance, or in the case of ,say, a 3 Ohm normal resistor. This gives a false illusion as if the effect of Lenz law would be weaker in this setup with the LED as the load. IT IS NOT.
rgds, Gyula
Dead right Gyula!!!
Mr Lenz is not so easily beaten,if at-all!!
peter