What is Self inductance: Definition and 42 Discussions

Inductance is the tendency of an electrical conductor to oppose a change in the electric current flowing through it. The flow of electric current creates a magnetic field around the conductor. The field strength depends on the magnitude of the current, and follows any changes in current. From Faraday's law of induction, any change in magnetic field through a circuit induces an electromotive force (EMF) (voltage) in the conductors, a process known as electromagnetic induction. This induced voltage created by the changing current has the effect of opposing the change in current. This is stated by Lenz's law, and the voltage is called back EMF.
Inductance is defined as the ratio of the induced voltage to the rate of change of current causing it. It is a proportionality factor that depends on the geometry of circuit conductors and the magnetic permeability of nearby materials. An electronic component designed to add inductance to a circuit is called an inductor. It typically consists of a coil or helix of wire.
The term inductance was coined by Oliver Heaviside in 1886. It is customary to use the symbol



L


{\displaystyle L}
for inductance, in honour of the physicist Heinrich Lenz. In the SI system, the unit of inductance is the henry (H), which is the amount of inductance that causes a voltage of one volt, when the current is changing at a rate of one ampere per second. It is named for Joseph Henry, who discovered inductance independently of Faraday.

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  1. Hak

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  4. E

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  5. L

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  6. warhammer

    I Guidance Requested on Inductance Formula for Solenoid

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  7. harsh22902

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  8. J

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  9. J

    What does self induction per unit length signify?

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  10. R

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  11. W

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  12. Z

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  13. M

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  14. cheapstrike

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  15. G

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  16. Conductivity

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  17. L

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  18. Amr Elsayed

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  19. A

    What is the self inductance of a circular loop of wire?

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  20. PratyashAstro

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  21. D

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  22. L

    Self Inductance of a Solenoid Problem

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  24. R

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  25. E

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  26. I

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  27. B

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  28. T

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  29. C

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  30. L

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  31. A

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  32. I

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  33. D

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  34. A

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  35. N

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  36. N

    Why is the formula for magnetic field not divided by length in this image?

    http://i26.tinypic.com/250tkyh.jpg the formula for magnetic field is like they show but its not divided by l like they did i can't see a reason why they present it that way ??
  37. N

    The logic of the self inductance formula

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  38. T

    How Does Self Inductance Affect Current Over Time in an R-L Circuit?

    Homework Statement Give a definition of (self) inductance. Suppose a battery, which supplies a constant EMF ϵ_0 is connected to a circuit of resistance R and inductance L at t = 0. Find an expression for the current as a function of time. Homework Equations V = IR V =...
  39. S

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  40. E

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  41. S

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  42. M

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    hey, i was just confused here, which is the right formula for finding the self inductance of a solenoid, given the number of turns, the cross-sectional area, the length, and the current. is it L = Uo x Ur x N^2 x A / L (Uo = mu o, Ur = mu r)?? pls if it is wrong, let me know the right...
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