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Given A = –yax + xay – zaz = ρaφ – zaz. Verify Stokes’ theorem for the circular bounding contour in the xy plane; check the result for: a) The flat circular surface in the xy plane b) The hemispherical surface bounded by the contour c) The cylindrical surface bounded by the contour

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Solve for the potential & EFI in the vicinity of a conducting cylinder (posses an infinite length) in a uniform EFI E0. The permittivities of the enviroment & the cylinder are ε1 & ε2 respectively. EFI is perpendicular to the cylinder’s axis

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Plane Wave Reflection at Oblique Incidence Angles (8) reflected p ( 0.144) 0.021 2 incident transmitted 1 1 ( 0.144) 0.979 p incident A uniform plane wave is incident from air onto glass at an angle of 30o from the normal. Find the fraction of the incident power that is reflected and transmitted for (a) p – polarization, & (b) s – polarizati...

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Define inductance of a coil as: • A.k.a self-inductance • Φ: magnetic flux • N: number of turns • I: current flowing in the coil • H (henry) ↔ weber-turn/A • Stands for linear inductor

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Maxwell’s First Equation (2) • Apply to electrostatic & steady magnetic fields • The electric flux per unit volume leaving a vanishingly small volume unit is exactly equal to the volume charge density there

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Energy Density in the Electrostatic Field (1) • Carrying a positive charge (1) from infinity into the field of another fixed positive charge (2) needs work • If the charge 1 is held near the charge 2, it has a potential energy • If then the charge 1 is released, it will accelerate away from the charge 2, acquiring kinetic energy • Problem: f...

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Using Field Sketches to Estimate Capacitance (1) • A conductor boundary is an equipotential surface • The electric field intensity E & the electric flux D are both perpendicular to the equipotential surfaces • E & D are perpendicular to the conductor boundaries & posses zero tangential values • The lines of electric flux, or streamlines, begi...

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Dipole: the plane between the 2 charges is zero potential • That plane can be represented by a vanishingly thin conducting plane, infinite in extent • → the dipole can be substituted for a system of a charge and a conducting plane, & then the fields above the conducting plane obtain equivalence

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Sheet Charge (1) • Charge is distributed on the surface of a plate (e.g. of a parallel-plate capacitor) • Sheet/surface charge density ρS (unit: C/m2)

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Stepping Motors (2) • The angular resolution of a VRM is determined by the number of rotor & stator teeth & can be greatly enhanced by techniques such as castleation. • Have a wide variety of designs & configurations. • The use of permanent magnets in combination with a variable-reluctance geometry can significantly enhance the torque & po...

44 trang | Chia sẻ: linhmy2pp | Ngày: 18/03/2022 | Lượt xem: 205 | Lượt tải: 0