Conventional current

Also called Current direction

Conventional current is current drawn and labelled in the direction positive charge would move. In an ordinary metal wire the actual carriers are electrons moving the other way, and every AP answer still uses the conventional direction.

Pick up any AP circuit diagram and the current arrows point the way positive charge would move. That is conventional current, and it is a choice rather than a discovery.

The CED states it in one line: the direction of conventional current is chosen to be the direction in which positive charge would move, and in common circuits the current is actually due to the movement of electrons, which are negative charge carriers. Both courses print that pair, at 11.1.A.2 in AP Physics 2 and 11.1.A.4 in AP Physics C: Electricity and Magnetism.

So in a copper wire the electrons drift one way and the labelled current points the other. Neither description is wrong. Negative charge moving left carries as much charge rightward past a cross section as positive charge moving right would, so the two bookkeepings agree on everything measurable.

The exam settles this for you, twice. A boundary statement under Topic 11.2 in both courses reads: unless otherwise specified, all circuit schematic diagrams will be drawn using conventional current. The AP Physics 2 equation sheet lists "Current is conventional current" among its exam conventions, and the AP Physics C: E&M sheet puts it as the direction of current being the direction in which positive charges would drift.

Use the conventional direction for right-hand rules, for Kirchhoff's loop rule signs, and for every arrow you draw on a circuit diagram. Electric current is the quantity; this is only which way it points.

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