electromotive force

Examples of electromotive force in the following topics:

• Sources of EMF

  • Electromotive force (EMF) is the voltage voltage generated by a battery or by the magnetic force according to Faraday's Law of Induction.
  • Electromotive force, also called EMF (denoted and measured in volts) refers to voltage generated by a battery or by the magnetic force according to Faraday's Law of Induction, which states that a time varying magnetic field will induce an electric current.
  • Electromotive "force" is not considered a force (as force is measured in newtons) but a potential, or energy per unit of charge, measured in volts.
  • Give examples of the devices that can provide the electromotive force

• EMF and Terminal Voltage

  • The output, or terminal voltage of a voltage source such as a battery, depends on its electromotive force and its internal resistance.
  • We call this potential difference the electromotive force (abbreviated emf).
  • Emf is not a force at all; it is a special type of potential difference of a source when no current is flowing.
  • Electromotive force is directly related to the source of potential difference, such as the particular combination of chemicals in a battery.
  • Express the relationship between the electromotive force and terminal voltage in a form of equation

• A Quantitative Interpretation of Motional EMF

  • A a motional EMF is an electromotive force (EMF) induced by motion relative to a magnetic field B.
  • An electromotive force (EMF) induced by motion relative to a magnetic field B is called a motional EMF.
  • Equating the two forces, we get $E = vB$.
  • In the conductor, however, we find an electromotive force, to which in itself there is no corresponding energy, but which gives rise—assuming equality of relative motion in the two cases discussed—to electric currents of the same path and intensity as those produced by the electric forces in the former case. "
  • Formulate two views that are applied to calculate the electromotive force

• Motional EMF

  • Motion in a magnetic field that is stationary relative to the Earth induces motional EMF (electromotive force).
  • As seen in previous Atoms, any change in magnetic flux induces an electromotive force (EMF) opposing that change—a process known as induction.
  • There are many connections between the electric force and the magnetic force.
  • That a moving magnetic field produces an electric field (and conversely that a moving electric field produces a magnetic field) is part of the reason electric and magnetic forces are now considered as different manifestations of the same force (first noticed by Albert Einstein).
  • This classic unification of electric and magnetic forces into what is called the electromagnetic force is the inspiration for contemporary efforts to unify other basic forces.

• Induced EMF and Magnetic Flux

  • Faraday's law of induction states that an electromotive force is induced by a change in the magnetic flux.
  • More basic than the current that flows is the electromotive force (EMF) that causes it.
  • Explain the relationship between the magnetic field and the electromotive force

• Changing Magnetic Flux Produces an Electric Field

  • We learned the relationship between induced electromotive force (EMF) and magnetic flux.
  • The number of turns of coil is included can be incorporated in the magnetic flux, so the factor is optional. ) Faraday's law of induction is a basic law of electromagnetism that predicts how a magnetic field will interact with an electric circuit to produce an electromotive force (EMF).
  • A device that can maintain a potential difference, despite the flow of current is a source of electromotive force.

• The Battery

  • Each half-cell has an electromotive force (or emf), determined by its ability to drive electric current from the interior to the exterior of the cell.
  • The electrical driving force across the terminals of a cell is known as the terminal voltage (difference) and is measured in volts.
  • The voltage of a battery is synonymous with its electromotive force, or emf.
  • This force is responsible for the flow of charge through the circuit, known as the electric current .

• Electric Generators

  • They induce an electromotive force (EMF) by rotating a coil in a magnetic field.
  • A generator forces electric charge (usually carried by electrons) to flow through an external electrical circuit.
  • Charges in the wires of the loop experience the magnetic force because they are moving in a magnetic field.
  • Charges in the vertical wires experience forces parallel to the wire, causing currents.
  • However, those in the top and bottom segments feel a force perpendicular to the wire; this force does not cause a current.

• Charging a Battery: EMFs in Series and Parallel

  • When voltage sources are in series facing the same direction, their internal resistances add and their electromotive force, or emf, add algebraically.
  • Compare the resistances and electromotive forces for the voltage sources connected in the same and opposite polarity, and in series and in parallel

• The Loop Rule

  • In other words, the sum of the electromotive force (emf) values in any closed loop is equal to the sum of the potential drops in that loop (which may come from resistors).
  • Another equivalent statement is that the algebraic sum of the products of resistances of conductors (and currents in them) in a closed loop is equal to the total electromotive force available in that loop.