mutual inductance(sec. 30.1) self-inductance and inductors(sec. 30.2) magnetic field energy(sec....
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Mutual Inductance (sec. 30.1) Self-inductance and inductors (sec. 30.2) Magnetic field energy (sec. 30.3) RL circuit (sec. 30.4) LC circuit (sec. 30.5) RLC series circuit (sec. 30.6)
Inductance Ch. 30
C 2009 J. Becker
The current i1 in coil #1 gives rise to a flux
through coil #2. If i1 changes, an emf is
induced in coil #2 (and vice versa) according to
Faraday’s Law:
MUTUAL INDUCTANCE
C 2004 Pearson Educational / Addison Wesley
where MUTUAL INDUCTANCE is
An inductor (L) – When the current in the circuit changes the flux changes, and a self-induced emf appears in the circuit. A self-induced emf always opposes the change in the current that produced
the emf (Lenz’s law).
SELF-INDUCTANCE (L)
Across a resistor the potential drop is always from a to b. BUT across an inductor an increasing current causes a potential drop from a to b; a decreasing
current causes a potential rise from a to b.
(a) A decreasing current induces in the conductor an emf that opposes the decrease in current.
(b) An increasing current induces in the inductor an emf that opposes the increase. (Lenz’s law)
c. Physics, Halliday, Resnick, and Krane, 4th edition, John Wiley & Sons, Inc. 1992.
A resistor is a device in which energy is irrecoverably dissipated.
Energy stored in a current-carrying inductor can be recovered when the current decreases to zero and the B field collapses.
P = Vab i = i L di/dt
dU = L i di
Energy density of B field is
Power = energy / time
P = Vab i = (i R) i = i 2 R U = i 2 R (time)
Oscillation in an LC circuit. Energy is
transferred between the E
field of the capacitor and the B field of the inductor.