Self inductance of a coil : how does it happen ? I've got some hardtime trying to imagine how it happens , the phrase which confused the most while studying was "each turn acts as a small magnet ",so why does it change polarities at the moment of switching the circuit on or off ? Also the whole concept of an induced current is kinda hard to understand , I can barely understand it ! I mean ,does the magneic field affect the free electrons of a conductor , so they move ?According to this idea , we can induce a current in all metals ... also, is there any other way to calculate self-inductance coefficient? One that doesn't include magnetic flux lines , magnetic in duction (B) ,cross sectional area of coil and time ,perhaps? Smethings which involves only current intensity and induced Emf ? If you answer these questions , I'd be forever indebted to you , afterall,my studies depend on this ,thank you so much in advance !