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Magnetism. INEL 4151 Dr. Sandra Cruz-Pol Electrical and Computer Engineering Dept. UPRM. Applications. Motors Transformers MRI More…. H= magnetic field intensity [A/m] B = magnetic field density [Teslas]. Biot-Savart Law. States that:. Example. a 2. a f. a 1. r.
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Magnetism INEL 4151 Dr. Sandra Cruz-Pol Electrical and Computer Engineering Dept. UPRM
Applications Motors Transformers MRI More…
H= magnetic field intensity [A/m] B = magnetic field density [Teslas]
Biot-Savart Law • States that:
Example a2 af a1 r For an infinitive line filament with current I (a1=180o and a2=0o):
PE. 7.1 Find H at (0,0,5) z • Due to current in (figure): where a1=90o and (0,0,5) 1 y 10A 1 x
Ampere’s Law • Simpler • Analogous to Gauss Law for Coulombs • For symmetrical current distributions
Ampere’s Law We define an Amperian path where H is constant.
Infinitely long coaxial cable z Four cases: 1) For r<a
Infinitely long coaxial cable z Four cases: 2) For a<r<b
Infinitely long coaxial cable Four cases: 3) For b<r<b+c z
Infinitely long coaxial cable Four cases: 4) For r>b+c
Sheet of current distribution z Cross section is a Line! b The H field on the Amperian path is given by: a y K [A/m] x
PE. 7.5 Sheet of current Plane y=1 carries a current K=50 azmA/m. Find H at (0,0,0). y K =50 z -x