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Now turning to the doctors we will talk about inductions defines physical construction how construction

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affects values in Doctor performance with AC and DC counts as you can see here.

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This is the inductor symbol and.

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And doctors are essentially called a file that are used to store energy temporarily in a magnetic field.

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And doctors when combined with capacitors are used in many different kinds of electronic circuits because

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of their brutality to oscillate or ring energy in one component feeds Darla back and forth in an oscillating

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or ringing manner at a specific frequency.

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This phenomenon is called resonance additionally but built in doctors in close proximity with overlapping

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magnetic field allow energy to flow from one inductor to the other by inducing a current in the other

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conductor.

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This is basically how a transformer works.

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These concepts are beyond the scope of this basic course.

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However the audience should be aware of the basic function of the conductor.

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Now there are two fundamental principle of electronics.

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One moving electrons create a magnetic field 2 moving or changing and will not take field cause electrons

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to move or to move and inductor as a call or fire throw which electron moves.

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And energy is stored in the resulting magnetic field like capacitors and doctors to more store energy.

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Unlike other stores and doctors store energy in a magnetic field not an electric field.

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When the source of electronic electrons is removed the magnetic field collapse immediately

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as you can see this is a conductor that has gone on passing through it.

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This is the magnetic field.

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Now the inductor are simply a the file can be Air One.

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Nothing in the middle of the core of the cord.

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Just like this one can be formed around a bear.

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Maybe it can be wondered out a bit more.

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Material material that concentrates magnetic field just like this example or this example can be on

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the round a circular form Troy like this one and the second example is this one one.

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And if nothing is in the middle it's like this one so depending on the core it can have different personalities

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and doctrines as much out in Henry.

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Henry is a measure of the intensity of the magnetic field that is produced typical indicate or values

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used in electronics are in the range of merely Henry one divide by 1000 and microfilm the one divided

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by one or by one million um.

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Let's look at the amount of conductance.

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Uh as we uh know the amount of everything is affected by a lot of value.

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The amount of conductance is influenced by a number of factors.

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Number of called in number of these turns diameter of call the diameter of this coil.

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This is the diameter from here to here.

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Spacing between in the space between each one.

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Then on the other side of the world used the size the thickness and the type of material inside the

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coin.

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So if its air fits Um metal core it will affect the amount of conductance.

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As you can see here this is the Air Corps.

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This is the iron core.

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This is the soft iron on call.

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This is a large diameter.

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This is a small diameter and this is uh close basing between turns inductor and this is uh wide spacing

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between cores and doctor all of these affects the doctrines of an inductor.

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Now inductor before months with this occurrence when this current is applied to an inductor the wire

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in the inductor momentarily appears as a short circuit and a maximum current flows as the magnetic field

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builds charges.

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There is a tendency for the current flow to slow down due to an position cause in the charging magnetic

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field or the changing will atrophy.

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Finally the magnetic field is at its maximum and the current flows to maintain the field as soon as

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the current source is removed the magnetic field begins to collapse and creates a rush of current in

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the other direction sometimes at very high voltage while conductors performance with AC currents.

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When AC current is applied to an inductor during the first half of the cycle the magnetic field builds

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as if it were a DC voltage during the second or the next half of the cycle.

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The current is reversed and the magnetic field first has to decrease the reverse polarity in step with

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the changing current depending on the value of the inductions.

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These forces can work against each other making for a less than symbol situation

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now because the magnetic field surrounding and inductor can cut across another inductor in close proximity.

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The changing magnetic field in one can cause current to flow and the other which is the basic of transformers

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as you can see in this example.

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This is a simple transformer beds of conductors in close proximity is another bottle use of conductors

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and electronics.

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Thus will transform other converts hundred twenty volt AC world current into current that will run at

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will volt DC radio will use a transformer and other circuits to do that conference.

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The conversion is important to go back to the two fundamental principles stated earlier in this unit.

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Moving electrons weird magnetic fields and changing magnetic fields cause electrons to move.

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This would be a good opportunity to walk your yourself through the process while uh see how transformative

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the work in the next lesson we will talk about diodes.

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Thanks for watching.

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This is education an engineering team.