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Can anybody explain why the 'clock rule' has been designed the way it is?

I mean, why is it that the polarity is North pole, if current flows in the anticlockwise sense as viewed from above and vice-versa.

What is the reason behind assigning the different fingers in Fleming's left or right hand rule? Why do we assign the thumb to the motion of conductor, the finger for the magnetic field and the middle finger for current?

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    $\begingroup$ It's literally just a convention; as far as I know there is no particular reason to choose one direction over another; it just results in sign differences. $\endgroup$
    – aquirdturtle
    Commented Feb 7, 2016 at 19:05
  • $\begingroup$ @aquirdturtle is correct. Basically, the cross product is only defined up to a sign, and we use the right-hand rule to define it as opposed to a left-hand rule. Everything that requires a cross product to be defined is then dependent on this choice as well. Or, in fancier mathematical language, the Hodge dual is only defined up to a sign. $\endgroup$
    – Michael Seifert
    Commented Aug 15, 2016 at 15:33

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By observing the direction of current in the anticlockwise direction, you see a capital N (for North Pole); in clockwise direction, you see a capital S (for South Pole). Try it on a piece of paper. However, as stated above, it's just a convention.

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