CH21 AC circuits and EM waves [ 21 .1] AC generator: ∆v=∆V max sin 2πft [ 21 .2] I rms = I max / sprt (2) Also important: P = I rms ^2 R [ 21 .3] V rms = V max / sprt (2) Resistance [ 21 .4a] ∆V (R,rms) = I rms * R [ 21 .4b] ∆V (R,max ) = I max * R Capacitors: [ 21 .5]X C = 1 / (2 π f C) [ 21 .6] ∆V (C,rms) = I rms * X C Inductors [ 21 .8] X L = 2 π f L [ 21 .9] ∆V (L,rms) = I rms * X L RLC Series Circuit i=I max sin 2πft impedance Z of circuit: [21.x] Z = sqrt ([R 2 + (X L – X C ) 2 ]) [ 21.x] ∆V max = I max * Z ∆V rms = I rms * Z [21.x] tan = (X ϕ L – X C ) / R Power in AC Circuit [21.x] P av = I 2 rms R [21.x] P av = I rms ∆V rms cos , cos is power factor ϕ ϕ Resonance in a series RLC Circuit [21.x] f0 = 1 / (2π sqrt (LC)) CH22 Reflection and Refraction Refraction: Index of refraction , n: N = speed of light in vac / speed of light in medium = c/v Frequency does not change, speed and wavelengths change. [22.x] SNELLS LAW n 1 sin ϴ 1 = n 2 sin ϴ 2 Total internal reflection ϴ c = critical angle where ϴ 2 = 90 Light goes from high n to low n, ie glass to air
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This note was uploaded on 11/03/2008 for the course PHYS 142 taught by Professor Coleman during the Spring '08 term at Emory.