Solving AC Circuits

1. All signals are in cosine, so sin signals need to be converted to cosine by shifting by 90 degrees: sin(x) = cos(x-90°)
2. All cosines can be represented in phasers: Amplitude x Degree
   ・v(t) = 10cos(100t - 30°) Volts
   ・Phaser v = 10 @ -30° = 10 e^(-j*30°)
3. Convert passive elements into impedances (Z)
   ・Z of a conductor is: 1/(jwC)
   ・Z of an inductor is: jwL
   ・Z of a resistor is: R
4. Solve the phasor circuit: V = I*Z (one can use KVL, KCL, Nodal, Mesh, Superposition)
5. Take phasor answer back to cosine
   ・i = 2 @ 15°　⇨　i(t) = 2cos(100t + 15°) Amps