Thanks but actually I need a more detailed answer.I think when the switch is in off position suddenly there is increase in resistance than of conductor because the medium is air now.
so, the molecule get energized and leave some spark especially in DC!
Thanks Jony. I am waiting for the chapter!If you don't know the answer now. Do not worry, in chapter 5 you will find more about this crossover losses.
As for the spike what about parasitic inductance?
Any voltage spikes are generated by the stray circuit inductance. This inductance tries to keep the current flowing, generating a spike when this flow is interrupted by the switch.Could anybody explain this more?
Why there is a voltage spike during turn-off period?
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