According to Fleming's left hand rule, the thumb represents the force, and the index finger represents the magnetic field direction.
Fleming’s Left-Hand Rule and Fleming’s Right-Hand Rule are essential rules applicable in magnetism and electromagnetism.
John Ambrose Fleming developed them in the late 19th century as a simple way of working out the direction of electric current in an electric generator or the direction of motion in an electric motor.
It is important to note that these rules do not determine the magnitude; instead show only the direction of the three parameters (magnetic field, current, force) when the direction of the other two parameters is known.
