Phase Behavior of RL Circuits: Explained

AI Thread Summary
The discussion revolves around the phase behavior of voltages in RL circuits, specifically addressing why the voltages across the resistor and inductor are always out of phase. It questions the assumption that at resonance, impedance equals resistance, suggesting that this would imply in-phase voltages across the generator and resistor. Participants suggest that solving the differential equation derived from Kirchhoff's laws could provide clarity on the phase relationships. The consensus emphasizes that despite resonance conditions, the inherent properties of inductors and resistors lead to phase differences. Understanding these relationships is crucial for analyzing RL circuit behavior accurately.
driedupfish
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Homework Statement



http://img14.imageshack.us/img14/7694/picture1yao.png

second part: the voltages across the resistor and the inductor are...

The answer given is always out of phase. Can someone explain why?
If the it is in resonance, wouldn't the impedance be equal to the resistance? Therefore, voltage across the generator and the resistor would be in phase?
The answer given for the second part is also always out of phase. Can someone explain that as well?
Thanks
 
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Perhaps if you solved the differential equation obtained using Kirchoff's laws for voltage it might give you some insight.
 
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