Current flow from positive to negative terminal in a circuit. But the charges which are moving in the circuit are the electron that is moving from the negative terminal to the positive terminal. Why we chose the opposite direction as electric current, not the real one?
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But the charges which are moving in the circuit are the electron moving from the negative terminal to the positive terminal
This is not generally true. In a typical circuit you may have negative electrons as charge carriers in wires, with negative electrons in n-type semiconductors, positive holes as charge carriers in p-type semiconductors, and both positive and negative ions as charge carriers in batteries. And outside of ordinary circuits you can get both positive and negative charge carriers in plasmas and particle beams. To make a blanket statement that the charge carriers are always negative is simply wrong.
Why we chose the opposite direction as electric current, not the real one?
Why should an electron be positively charged? It has no more claim than a proton.
In any case, the stated direction of current flow is the real one. What matters in Maxwells equations is the current density $\vec J= \rho \vec v$. If $\rho<0$ then $\vec J$ correctly points in the opposite direction of $\vec v$. And all of the electromagnetic effects depend on $\vec J$, not $\vec v$. So there is no sense in which it is the wrong direction.
In dealing with circuits you may as well ignore electrons and just think about the actual electric current which goes from positive to negative regardless of the sign of the charge carriers
Dale
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Well, this is easy to answer. The current flow is determined by the direction of the electric field. It was thought that the positive charges was the moving charges so, when EM theory was being discovered, everything was doing in that base. This is why the direction of the current flow follows the natural move of the positive charges, but the real flow, goes in the other way.
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