1. 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
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2. L C
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3. L C
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4. L C
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5. 1 2 3 4 5 6 7 8
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9. L C
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13. O
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17. 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
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19. O A B
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20. O A B
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24. (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
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