Physics · Ch 4 — Electromagnetic Induction and Alternating Current
Fleming's Right Hand Rule
Fleming's Right Hand Rule
For the common case of a straight conductor physically moving through a magnetic field, Fleming's right hand rule offers a fast mechanical shortcut for finding the induced current's direction, without needing to work through the flux-change-and-Lenz's-law reasoning explicitly each time. The rule: hold the thumb, index (fore) finger and middle finger of the right hand mutually perpendicular to one another (like the three edges meeting at a corner of a box). If the index finger is pointed along the direction of the magnetic field, and the thumb is pointed along the direction of motion of the conductor, then the middle finger automatically points along the direction of the induced current in the conductor. …
What this figure shows. A hand diagram shows the thumb, index (fore) finger and middle finger of the right hand held mutually perpendicular to one another, like the three edges of a corner of a box. Labels identify the thumb as pointing along the 'Direction of motion of the conductor', the index finger as pointing along the 'Direction of field' (from the N pole to the S pole of a magnet shown flanking the diagram), and the middle finger as pointing along the 'Direction of Current' induced in the conductor. The rule -- also called the generator rule, since it describes the situation inside an electrical generator where a conductor is mechanically moved through a field -- lets the induced current's direction be read off directly f …