Electromagnetic Oscillations and Alternating Current Chapter 31 Electromagnetic Oscillations and Alternating Current In this chapter we will cover the following topics: -Electromagnetic oscillations in an LC circuit -Alternating current (AC) circuits with capacitors -Resonance in RCL circuits -Power in AC-circuits -Transformers, AC power transmission (31 - 1)

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SUMMARY Circuit element Average Power Reactance Phase of current Voltage amplitude Resistor R Current is in phase with the voltage Capacitor C Current leads voltage by a quarter of a period Inductor L Current lags behind voltage by a quarter of a period (31 - 17)

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(31 - 24) Transmission lines Erms =735 kV , I rms = 500 A home Power Station Transmission lines Erms =735 kV , I rms = 500 A home 110 V T1 T2 Step-up transformer Step-down transformer R = 220Ω (31 - 24)

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