Magnetism Flashcards
Equation (p5) for the element of force dF on an element of current-length Idl in a magnetic field dB:
Magnetic flux (p8) is the sum over an area of the density of magnetic flux through that area:
The Lorentz force (p14) on a particle with charge q moving with velocity v in electric E and magnetic B fields:
Hall effect (p18): magnetic Lorentz force on charge carriers carrying a current in a magnetic field leads to Hall voltage:
Torque on a current loop (p27) of vector area A = Anˆ carrying current I in magnetic field B:
The Biot-Savart Law (p33) for the element of magnetic field dB at distance r from currentlength element Ids:
Standard results derived from Biot-Savart Law: (a) field of a current-carrying long straight wire (p35):
Standard results derived from Biot-Savart Law:
field of a current carrying circular loop (on axis) (p41)
Magnetic force between current carrying wires (p49):
Amp´ere’s Law (p50):
Standard results derived from Amp´ere’s Law (a) field of a current-carrying long straight wire (p51):
Standard results derived from Amp´ere’s Law (b) field of a solenoid
Standard results derived from Amp´ere’s Law
field of a toroid
Magnetic field of an infinite conducting sheet:
Definition of magnetic susceptibility (p3), χm in terms of applied field B0 and induced field Bm:
Defintion of relative permability (p3, p24), µr in terms of total field inside material:
Classification of magnetic materials (p3):
Langevin paramegnetic equation (p13) for magnetization:
Curie’s Law (p13) for small magnetic fields or large temperatures:
Magnetization of ferromagnetic materials (p18):
Magnetic intensity definitions (p19):
Continuity at an interface between media (p21):
Contributions from free and bound currents (p25):
Gauss’ Law for magnetism (p9)in differential form:
and in integral form
Boundary conditions on B and H (p15):
Stokes’ Theorem (p19):
The Amp´ere-Maxwell Law in integral form (p20):
The Amp´ere-Maxwell Law in differential form (p26):
Faraday’s Law for induced emf (electromotance) (p29):
Self-inductance (p42): the induced back enf is proportional to the rate of change of current
RL circuit (p45): behaviour after switch is closed. By applying Kirchhoff’s loop rule:
Energy density in a magnetic field (p49):
LC circuit (p52): (zero resistance ⇒ zero damping) charge on capacitor oscillates at angular frequenc
Damped oscillations in RLC circuit (p57): resistance introduces damping
Phasors (p9):
Phasors in ac circuits (p9):
Complex number representation (p16):
RLC circuit complex impedance (p18):
RLC circuit at resonance, ω = ω0 (p20):
Average power in RLC circuit (p30):
Resonance in RLC circuit (p32):
Q-factor (p32):
Maxwell’s equations in differential and integral form (p4):
The wave equation in free space (p6):
The Poynting vector represents the flux of energy density in the wave (p8):
Average energy density passing a plane is the intensity or irradiance (p9):
