Induction - Definition, Difference, FAQs
Define Self Inductance.
Induction definition (Inductance definition) and Induction meaning (Induce meaning): Magnetism is mainly made up of magnetic fields whose strength is proportional to the rate at which they change. Induction is defined in this way for conductors. The SI unit of self-inductance is Henry, which represents the inductance(L). The discovery of induction is generally attributed to Michael Faraday, and its mathematical description is known as Faraday's law of induction. Induced fields are described by Lens's law. Magnetic induction is used in many devices, such as motors and generators, and electrical components such as inductors and transformers.
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History
Michael Faraday discovered electromagnetic induction in 1831 and published his findings. In 1832, Joseph Henry independently discovered it.
The first experiment Faraday conducted (August 29, 1831) included wrapping two wires around opposite sides of an iron ring or "torus". His understanding of electromagnetism suggested that, as the current passed through an arm, an electrical effect would follow. Connect the other wire to the battery after plugging one wire into the galvanometer. As soon as the wire was connected to the battery, he saw transient currents, which he called "waves of electricity."
Inductions can occur due to shifts in magnetic flux caused by connecting and disconnecting the battery. The electromagnetic induction phenomenon was discovered by Faraday two months after it was first observed. A bar magnet was slid rapidly in and out of a coil of wires, and a copper disk with a sliding electrical lead was rotated nearby to produce a steady (DC) current (Faraday's disk).
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Factors Affecting Inductance
Inductance is affected by the following factors:
Inductor turns measure how many turns there are in the wire.
In the core is a material used.
The shape of the core.
According to Faraday, electromotive forces are induced in a circuit when the magnetic flux changes. Induction may be understood as the result of Faraday's law of electromagnetic induction. A change in inductance at a particular time is characterized by the electromotive force generated in opposition to it.
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Difference between Self-Inductance and Mutual Inductance
Self-induction | Mutual induction |
is the coil's self-inductance. | The mutual inductance of a pair of coils is it's characteristic. |
| When the coil's main current decreases, the induced current opposes the decay of the coil's current. | If the coil's main current decreases, the induced current developed in the neighbouring coil opposes that decline. |
| Whenever the coil's main current increases, the induced current opposes it. | A neighbouring coil develops induced current when the main coil's current increases, and this impedes the coil's growth. |
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Inductance Derivation
With the switch on, consider a DC source. Turning on the switch causes the current to flow from zero to a certain value, which results in an increase in the flow of current. Let φ represent the flux change caused by current flow. Time is the factor determining the flux change, and it is given as:
d∅/dt
Using Faraday's law of electromagnetic induction,
E = -Nd∅/dt
Inductance is calculated using the modified equation above
E = -N d∅/dt
E = -L di/dt
N d ∅ = L di
NΦ = Li
Therefore,
Li = NΦ = NBA
Were,
B stands for flux density
In coils, A is the coil area
Hl = Ni
Were,
An electric field creates a magnetic field, which is called H
B = μ H
Li = NBA
L = NBA/ i = N2BA/Ni
N2BA/Hl = N2μHA/Hl
L = μN2A/l
NCERT Physics Notes:
Mutual and self-inductance examples
Example 1. An iron core that has a relative permeability of 800 winds a 500-turn solenoid with 500 turns. The length of the solenoid is 40 cm, and its radius is 3 cm. A change from 0 to 3 A has taken place in the current. You can calculate the average emf induced by this change in current for the duration of 0.4 seconds.
Solution:
Given:
No. of turns, N = 500 turns
Relative permeability, μr = 800
Length, l = 40 centi meters = 0.4 metres
The radius, r, equals 3 cm = 0.03 m
Change in the current, di = 3 - 0 = 3 A
Change in time, dt = 0.4 sec
As a result of self-induction, we get
L = μN2A/l = μ0μrN2?r2/l
We obtain the following values after substituting
L = 1.77 H
Magnitude of the induced electromagnetic field, ε = L di/dt = 1.77×3/0.4
ε = 13.275 V
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Frequently Asked Questions (FAQs)
Henry is the SI unit of inductance.
One Henry is defined as the amount of inductance required to produce an emf of one volt in a conductor when the current change in the conductor is at the rate of One Ampere per second.
Inductance is affected by the following factors:
A measure of how many turns is in the wire of the inductor.
the core material used.
The shape of the core.
There is an opposite induced electromotive force when there is a change in current or magnetic flux in the coil. Self-Induction is the phenomenon responsible for this behaviour. The magnetic flux is directly proportional to the current passing through the coil when the current starts flowing through it at any time.
Mutual Induction Definition: It is necessary to place two coils near each other. Coils P and S refer to primary (primary coil) and secondary (secondary coil) coils, respectively. With the P-coil, a battery and a key are attached while with the S-coil, a galvanometer connects across it. An opposing electromotive force is produced across each coil when the current or magnetic flux varies between two coils, and this phenomenon is called Mutual Induction.
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Solution : The correct answer is (c) Employee benefits
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Correct Answer: Outsourcing training
Solution : The correct answer is (d) Outsourcing training
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Correct Answer: Employee benefits
Solution : The correct answer is (c) Employee benefits
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Correct Answer: Statement 1 is false and statement 2 is true.
Solution : The internal source of recruitment prevents induction of fresh talent. By stopping in fusion of new blood into the organisation it may also lead to in breeding that is existing employees may continue to work and behave in old ways even after promotion and transfer.
Hence, option D is correct.
Correct Answer: The assertion is true, but the reason is false.
Solution : The correct answer is (c) The assertion is true, but the reason is false.
The assertion is true. Induction programs are indeed designed to familiarize new employees with the organization, its culture, policies, and procedures.
The reason is false. Induction is not primarily focused on testing technical skills; instead, its primary focus is on providing information and support to help new employees integrate into the organization effectively.