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

Find impedance and Io.

draw phasor diagram for rlc circuit

V = 120cos(2π525t) where R = 10Ω, C = 1μF, L = 100mH, Vo = 120V

2. Relevant equations

Z = √(R2 + (ωL-1/(ωC))^2) = √(10^2 + (2π * 525 Hz * 100 mH - 1/(2π * 525 Hz * 1 μF ))^2) = 28.525Ω

Io = Vo/Z = 120 V / 28.525 Ω = 4.207 A

tan ϕ = (ωL - 1/(ωC))/R = (2π525 * 100 mH - 1/(2π525 *1 μF)) / 10 Ω = -15882.508

ϕ = -1.5707 rad = -89.996°

V_{Ro}= IoR = 4.207 A * 10Ω = 42.07 V

V_{Co}= Io/(ωC) = 4.207 A / (2π525 * 1 μF) = 1275.361611 V

V_{Lo}= IoωL = 4.207 A * 2π525 * 100 mH = 1387.751431 V

Vo = √(V_{R0}^{2}+ (V_{Lo}- V_{Co})^2 ) = 120.0056523 V

3. The attempt at a solution

I get a negative phase angle which should mean that capacitance is greater than inductance but this is not the case based on values above.

when I draw out a rough phasor diagram I have voltage ahead of current.

not sure where i went wrong.

note: diagram attached is rough and not to perfect scale

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# Homework Help: Rlc problem: calculations of components and phasor drawing

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