I'm curious about the origin of this convention. If we decided field lines went from south to north then the field lines would go anticlockwise not clockwise. I was watching a youtube video on the difference of winding a coil clockwise vs winding a coil counter clockwise
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It said the poles would be opposite using the same battery configuration.
But there is a clear reason why it is clockwise
Earth's spin cuases an apparent motion of the sun during the day, which causes shadows to turn around objects This was used to construct sundials to measure the time, and so the shadow's motion defined what we call clockwise, as the direction was transferred to later mechanical clocks. This means that if a current follows that curling, it goes to a higher voltage Or if it opposes that curling, it goes to a lower voltage
This same reverse rule can also be phrased as lenz's law. If you don't do this, then there really is no way to answer Calling one clockwise and the other anticlockwise doesn't quite get the difference across But the angular momentum is genuine
The north and south pole of a solenoid depends on two factors
Start by determine the positive pole of the power source (e.g Battery), then the end of the solenoid that you are going to connect to it Now, looking down the solenoid tube determine what direction is the winding The magnetic field doesn't go anywhere
We conventionally draw field lines going from north to south, but that's just a convention So the choice of clockwise vs anticlockwise is just a convention
