(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

There is a circuit with an alternating voltage source and a capacitor (capacitance C) an inductor (inductance L) and a resistor (resistance R). The resistor has a potential VR marked across it.

Calculate the magnitude and phase of the voltage VR.

2. Relevant equations

Impedance of resistor=R, impedance of capacitor=-j/wC, impedance of inductor=jwL, impendances in series add linearly.

3. The attempt at a solution

My first though was just to treat it as a potential divider and its easy to find the magnitude. But I'm getting at bit confused about finding the phase of VR: can you just take the phase from the potential divider equation, so pahse relative to input voltage=-arctan((wL-1/wC)/R)? Possibly it's me trying to make things harder than they should be but it's from a past exam paper and was worth 12 marks so doesn't seem to involve much work?

Thanks

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# Help with Impedances

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