Electromagnetic Field Theory II The Biot-Savart LawThe Biot-Savart Law The Biot-Savart Law is an equation that describes the magnetic field created by a current-carrying wire, and

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Ass. Prof. Dr. Hind S. HussainBy

Electromagnetic Field Theory II

Savart Law-Biot The

is an equation that describes the magnetic field created by a Savart Law-Biot The

its strength at various points. It carrying wire, and allows you to calculate-current

looks like this

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carrying filamentary conductor of finite determine the field due to a straight current

length AB as in Figure

for any straight

filamentary conductor of

finite length

when the conductor is semiinfinite point A is now at point A is now at (90, 0, 0) while B is at (0, 0, ∞);

α1, = 90°, α2 = 0°,

when the conductor is infinite in length: A is at (0, 0, - ∞) while B is at (0, 0, , ∞); α1= 180°, α2 = 0°,

where al is a unit vector along the line current and ap is a unit vector along the perpendicular line from

the line current to the field point.

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For a circular loop

By symmetry, the contributions along ap add up to zero because the radial components produced by

pairs of current element 180° apart cancel.

For solenoid of length l and radius a consists of N turns of wire carrying current

If l˃> a,

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AMPERE'S CIRCUIT LAW Ampere's circuit law states that the line integral of the tangential component of H around a dosed path

is the same as the net current Ienc. enclosed by the path.

By applying Stoke's theorem

APPLICATIONS OF AMPERE'S LAW

A. Infinite Line Current

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B. Infinite Sheet of Current

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C. Infinitely Long Coaxial Transmission Line

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Documents

Electromagnetic Field Theory II The Biot-Savart LawThe Biot-Savart Law The Biot-Savart Law is an equation that describes the magnetic field created by a current-carrying wire, and