electromagnetism In physics, electromagnetism is an interaction that occurs between particles with electric charge via electromagnetic fields. The electromagnetic force is one of the four fundamental forces of nature. It is the dominant force in the interacti ...

, Fleming's right-hand rule (for generators) shows the direction of induced current when a conductor attached to a circuit moves in a

magnetic field A magnetic field (sometimes called B-field) is a physical field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular ...

. It can be used to determine the direction of current in a generator's windings. When a conductor such as a wire attached to a circuit moves through a magnetic field, an

electric current An electric current is a flow of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is defined as the net rate of flow of electric charge through a surface. The moving particles are called charge c ...

is induced in the wire due to Faraday's law of induction. The current in the wire can have two possible directions. Fleming's right-hand rule gives which direction the current flows. The right hand is held with the

thumb The thumb is the first digit of the hand, next to the index finger. When a person is standing in the medical anatomical position (where the palm is facing to the front), the thumb is the outermost digit. The Medical Latin English noun for thumb ...

index finger The index finger (also referred to as forefinger, first finger, second finger, pointer finger, trigger finger, digitus secundus, digitus II, and many other terms) is the second digit of a human hand. It is located between the thumb and the m ...

and

middle finger The middle finger, long finger, second finger, third finger, toll finger or tall man is the third digit of the human hand, typically located between the index finger and the ring finger. It is typically the longest digit. In anatomy, it is al ...

mutually perpendicular to each other (at right angles), as shown in the diagram. * The thumb is pointed in the direction of the motion of the conductor relative to the magnetic field. * The first finger is pointed in the direction of the magnetic field. By convention, it's the direction from North to South magnetic pole. * Then the second finger represents the direction of the induced or generated current within the conductor (from + to −, the terminal with lower

electric potential Electric potential (also called the ''electric field potential'', potential drop, the electrostatic potential) is defined as electric potential energy per unit of electric charge. More precisely, electric potential is the amount of work (physic ...

to the terminal with higher electric potential, as in a voltage source) The bolded letters in the directions above give a mnemonic way to remember the order. Another mnemonic for remembering the rule is the initialism "FBI", standing for Force (or otherwise motion), B the symbol for the magnetic field, and I the symbol for current. The subsequent letters correspond to subsequent fingers, counting from the top: thumb → F; first finger → B; second finger → I. There is also a Fleming's left-hand rule (for

electric motors An electric motor is a machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a wire winding to generate Laplace force i ...

). The appropriately handed rule can be recalled from the letter "g", which is in "right" and "generator". These

mnemonic A mnemonic device ( ), memory trick or memory device is any learning technique that aids information retention or retrieval in the human memory, often by associating the information with something that is easier to remember. It makes use of e ...

s are named after British engineer

John Ambrose Fleming Sir John Ambrose Fleming (29 November 1849 – 18 April 1945) was an English electrical engineer who invented the vacuum tube, designed the radio transmitter with which the first transatlantic radio transmission was made, and also established ...

, who invented them. An equivalent version of Fleming's right-hand rule is the left-hand palm rule.Left-hand palm rule
Retrieved 2024/07/27

Distinction between the right-hand and left-hand rule

{{Excerpt, Fleming's left-hand rule for motors, Distinction between the right-hand and left-hand rule, only=paragraphs, hat=no

References

External links

Diagrams at magnet.fsu.edu

Diagrams and exercises
Science mnemonics Electromagnetism zh:佛來明右手定則

Distinction between the right-hand and left-hand rule

See also

References

External links