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Why transformer action can take place in DC and ac circuit?

First understand that every electrical conductor (wire) with current flow through it will produce an invisible magnetic field around it. This field is directly proportional to the magnitude of current flowing. Second (and inversely) realize that any conductor moving through a magnetic field will produce a voltage, And if provided with a complete circuit (a path to flow in) will result in current flow in that conductor. The movement can be from the conductor moving, or from the magnetic field moving, as long as there is 'relative motion' between the conductor and the magnetic field. In short, a conductor with current flow produces a magnetic field , a conductor and a magnetic field with relative motion between them produces current flow. (This is also the basis for how a motor works) AC means 'Alternating Current'! The current flow moves in one direction along a conductor, then reverses to zero and to equal magnitude in the opposite direction. Each time this current changes direction it produces a magnetic field, as it returns to zero the field collapses. As the current builds in the opposite direction the magnetic field builds again. In an AC transformer circuit, two conductors are placed in close proximity to each other and an alternating current is applied to the first conductor. This alternating current causes a magnetic field to build around the conductor, then collapse, build again in the opposite polarity and so on. This expanding and collapsing magnetic field creates relative motion between the field and the second conductor which then produces current flow of its own. This is called "transformer Action". In steady state DC circuits, the magnetic field is constant and there is normally no relative motion, therefore no "transformer action". There is however still a relative motion created when the circuit is first energized, and when it is de-energized. This collapsing field is how the ignition coil in your car works. In the simplest form, contacts (points) were opened by a cam, the open contacts de-energized the first conductor (the 12VDC primary). The resulting collapsing field cut across the secondary conductors. Because these conductors were wound into many turns or "coils" it actually multiplies the effect producing a high voltage in the secondary (connected to the ignition wires). This produced a voltage and current strong enough to jump across the gap of a spark plug. And, Yes Virginia, there is such a thing as a DC transformer.


What do you mean by eddy current loss?

Eddy currents are currents induced in conductors to oppose the change in flux that generated them. It is caused when a conductor is exposed to a changing magnetic field due to relative motion of the field source and conductor, or due to variations of the field with time. This can cause a circulating flow of electrons, or a current, within the body of the conductor. These circulating eddies of current create induced magnetic fields that oppose the change of the original magnetic field due to Lenz's law, causing repulsive or drag forces between the conductor and the magnet. The stronger the applied magnetic field, or the greater the electrical conductivity of the conductor, or the faster the field that the conductor is exposed to changes, then the greater the currents that are developed and the greater the opposing field.


Difference between statically and dynamically induced emf?

STATICALLY INDUCED EMFThe emf induced in a coil due to change of flux linked with it (change of flux is by the increase or decrease in current) is called statically induced emf.Transformer is an example of statically induced emf. Here the windings are stationary,magnetic field is moving around the conductor and produces the emf.DYNAMICALLY INDUCED EMFThe emf induced in a coil due to relative motion of the conductor and the magnetic field is called dynamically induced emf.example:dc generator works on the principle of dynamically induced emf in the conductors which are housed in a revolving armature lying within magnetic field


What 3 things are required to induce a voltage in a conductor?

three things required for electromagnet are hands eyes ears have fun! lol


What is the factors determining induced emf in dc machine?

The factors determining induced electromotive force (emf) in a DC machine include the strength of the magnetic field, the number of turns in the coil, the speed of rotation of the armature, and the angle of the coil relative to the magnetic field lines. The induced emf is directly proportional to the magnetic field strength, the number of turns in the coil, and the speed of rotation, while it is also affected by the angle of the coil in relation to the magnetic field. These factors collectively determine the magnitude of the induced emf in a DC machine.

Related Questions

What three things are required to produce EMF in an alternator?

Three things required to produce electromotive force (EMF) in an alternator are a magnetic field, a conductor, and relative motion between the magnetic field and the conductor.


How can magnet produce current?

A magnetic field can induce an electric current in a conductor when there is a relative motion between the magnetic field and the conductor, according to Faraday's law of electromagnetic induction. When a conductor is moved within the magnetic field or the magnetic field moves relative to the conductor, it creates a changing magnetic flux, which generates an electromotive force (EMF) that drives a current to flow in the conductor.


What three things needed to complete magnetic induction?

A changing magnetic field A conductor or coil of wire Movement between the magnetic field and the conductor (relative motion)


In what two ways is it possible to generate a higher voltage in a moving conductor?

Higher voltage can be achieved in a moving conductor by increasing the strength of the magnetic field it moves through or by increasing the speed at which it moves through the magnetic field. Both of these factors contribute to inducing a greater electromotive force (emf) in the conductor, resulting in a higher voltage output.


How induced current produce?

when a conductor moves accross a magnetic field or when magnetic field moves with respect to a stationary conductor for current to be induced, there must be relative motion between the coil and the magnetic.


How induced current is produce?

when a conductor moves accross a magnetic field or when magnetic field moves with respect to a stationary conductor for current to be induced, there must be relative motion between the coil and the magnetic.


When is induced electromotive force produced in a coil placed near a magnet?

An induced electromotive force is produced in a coil placed near a magnet when there is a relative motion between the coil and the magnetic field. This motion causes a change in the magnetic flux passing through the coil, leading to the generation of an electromotive force according to Faraday's law of electromagnetic induction.


Electromagnetic generators create current by moving what?

Generators tend to move the coild while alternators tend to move the magnets. Those are the only two choices you have to make power. The disadvantage of moving the wires (or coild) is that you really need brushes that wear.


What is the key when using a magnet and a conductor to induce a current in the conductor?

Motion


What is the difference between CEMF and EMF?

Only the relative direction they are moving. EMF, measured in Volts, travels along a conductor, perhaps because a magnetic field has built up around the conductor. When that magnetic field collapses, CEMF, or counter-EMF is generated in the conductor, and it travels in the opposite direction of the original EMF, countering the original flow of electricity. EMF is Electromotive Force, and is one component of measuring electricity. EMF is measured in Volts, and represents the 'pressure' moving the electricity along.


Motion magnetism and a conductor will create what?

Motion between a magnet and a conductor will induce an electric current in the conductor, according to Faraday's law of electromagnetic induction. This phenomenon is the basis for generating electricity in generators and power plants.


Why transformer action can take place in DC and ac circuit?

First understand that every electrical conductor (wire) with current flow through it will produce an invisible magnetic field around it. This field is directly proportional to the magnitude of current flowing. Second (and inversely) realize that any conductor moving through a magnetic field will produce a voltage, And if provided with a complete circuit (a path to flow in) will result in current flow in that conductor. The movement can be from the conductor moving, or from the magnetic field moving, as long as there is 'relative motion' between the conductor and the magnetic field. In short, a conductor with current flow produces a magnetic field , a conductor and a magnetic field with relative motion between them produces current flow. (This is also the basis for how a motor works) AC means 'Alternating Current'! The current flow moves in one direction along a conductor, then reverses to zero and to equal magnitude in the opposite direction. Each time this current changes direction it produces a magnetic field, as it returns to zero the field collapses. As the current builds in the opposite direction the magnetic field builds again. In an AC transformer circuit, two conductors are placed in close proximity to each other and an alternating current is applied to the first conductor. This alternating current causes a magnetic field to build around the conductor, then collapse, build again in the opposite polarity and so on. This expanding and collapsing magnetic field creates relative motion between the field and the second conductor which then produces current flow of its own. This is called "transformer Action". In steady state DC circuits, the magnetic field is constant and there is normally no relative motion, therefore no "transformer action". There is however still a relative motion created when the circuit is first energized, and when it is de-energized. This collapsing field is how the ignition coil in your car works. In the simplest form, contacts (points) were opened by a cam, the open contacts de-energized the first conductor (the 12VDC primary). The resulting collapsing field cut across the secondary conductors. Because these conductors were wound into many turns or "coils" it actually multiplies the effect producing a high voltage in the secondary (connected to the ignition wires). This produced a voltage and current strong enough to jump across the gap of a spark plug. And, Yes Virginia, there is such a thing as a DC transformer.