Fleming's left-hand rule helps determine the direction of the force on a current-carrying conductor in a magnetic field, or the direction of movement of a motor's coil. To use it, hold your left thumb, first finger (index finger), and second finger (middle finger) perpendicular to each other. The thumb shows the direction of the force or motion, the first finger indicates the direction of the magnetic field (from North to South), and the second finger shows the direction of the conventional elec