Electromotive force can be generated in various ways, such as heating thermocouples, chemical reactions, etc. The most popular and widely used method of generating electromotive force is based on electromagnetism.
Following the magnetic effects of an electric current, attempts have been made to create an electric current using magnetism rather than attracting it through the conductor carrying the current. It was invented in 1831 by the English physicist Michael Faraday, who managed to obtain an electromotive force from magnetic flux. Electromagnetic induction is the phenomenon in which an electromotive force is obtained through change.
Faraday's law of electromagnetic induction
According to Faraday's law of electromagnetic induction, a changing magnetic field induces an electromotive force in a conductor. This can happen in two scenarios: when a magnetic field moves relative to a stationary conductor or when a conductor moves through a static magnetic field. In both cases, the relative motion or change in magnetic field strength creates an induced voltage.
Electromotive force and potential difference
Let us first examine the experiment conducted by Faraday to understand magnetic force induction.
Consider a coil with N turns connected to a galvanometer. Fig. The meter shows the current flow within the circuit, if any. A static magnet is influenced relative to the coil and certain lines of magnetic force associated with the lock are changed. Whenever a movement of fixed interest occurs, the meter deviates and indicates the flow of current through the circuit.
Deflection continues as long as the magnet is moving. The faster the magnet is influenced, the greater the deflection. Currently, the deflection of the galvanometer indicates the flow of current. However, for electricity to flow, an electromotive force must be present. Therefore, such movement of the flux lines relative to the coil creates an electromotive force that drives current through the circuit. This may be the point where the latch on which the electromotive force is generated is fixed and the magnet is influenced to produce relative flux movement with respect to the shaft.
Principles and Applications
Electromagnetic induction is the basic operating principle of electrical generators that convert mechanical energy into electrical energy. In a generator, a rotating coil of wire is placed in a magnetic field. As the coil rotates, the magnetic field flowing through it changes, inducing an alternating current (AC) in the ring. This alternating current can then be used to power electrical devices.
Another important application of electromagnetic induction is transformers. Transformers use two coils, called primary and secondary, wound around a common iron core. When an alternating current flows through the primary coil, the magnetic field of the core changes. This changing magnetic field then induces a voltage in the secondary coil, allowing for efficient electrical energy transfer and voltage conversion.
Electromagnetic induction also finds application in devices such as induction cooktops, wireless charging systems, and magnetic sensors. It is a fundamental principle of electromagnetism and has revolutionized several industries by enabling the generation, transmission and use of electrical energy in our daily lives.
Magnetic effect of an electric current
The magnetic effect of an electric current, also known as electromagnetism, is a fascinating phenomenon that is at the heart of many technological advances. When an electric current flows through a conductor, it creates a magnetic field around it. This magnetic field is characterized by a direction and intensity that depend on the direction and intensity of the current.
For there to be an induced electromotive force, there would have to be the following:
- A coil or conductor.
- A magnetic field (permanent magnet or electromagnet).
- Relative movement between the conductor and the magnetic flux (achieved by moving the conductor relative to the instability or moving relative to the conductor)
Laws of magnetism
Similar observations can be obtained by moving a coil in the magnetic field of the attached static magnet, creating relative motion between the flux and the coil. This arrangement is also shown in Fig. Coil AB is influenced by some external pulses in the magnetic field of a fixed permanent magnet. The coil is connected to the measuring device.
The meter will show deflection when conductor AB is moved in the direction shown in the figure, indicating current flow through coil AB. Likewise, in a magnetic field, the greater the deflection, the faster the conductor will move.
In any case, what mainly occurs is a change in the flux lines in the conductor, that is, the flux lines are interrupted by the conductor, thus inducing an electromotive force.
In this experiment, the laws expressed by Faraday are called Faraday's laws of electromagnetic induction.
