Mammoth Memory

Section through a wire: electric flow convention

Looking at the cross section of a wire you see:

Section through a wire

But scientists needed a convention to show which direction electrical current flows through the wire.

They did so using the mnemonic of an arrow.

Arrow direction

Scientists said an arrow coming towards you would look like this:

Arrow head on


Arrow travelling away

And they said that an arrow fired away from you would look like this:

Current travelling away


Current travelling towards and away from you down a wire

This same convention works for the current direction in wires.

Current in a circuit moving towards you

The convention would be that the section through the wire is as follows:

Current travelling towards you


Now, with the battery turned around . . .

Current in a circuit moving away from you

. . . the current flow going away from you would have the convention:

Current travelling away down a wire


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