what' the differnece between a circular coil of wire of many turns and a solenoid.
Isn't that exactly what a solenoid is: a circular coil of wire with lots of turns in it?
Correct. But by 'popular' terminology, most people think of a solenoid as being a mechanical device consisting of a moveable core within the solenoid coil, as in an automotive starter or a model train track switch.
To me, a solenoid is a "stretched out" coil, that is, its geometry is a cylinder, and the length is significant.
thanks that seems logical now...becaus ei was working out through the formulaes for the magnetic field due to each....
so circular coil is a coil of negligible length and same radius
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