# Thevenin AC circuit

• Engineering

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## Homework Equations

Thevenin, Series, Parallel

## The Attempt at a Solution

j10(12-j34) / (j10+12-j34) = (340 + 120j) / (12/j24)

1.67 + j13.3 or 13.44∠82.4°

Now why can't I just use this equivalent resistance and multiply by the current source (22∠30°) to find the Thevenin Voltage? The result of doing this is 295.68∠112.8°V. Instead, the book uses Nodal Analysis to find VTH, which results in 295.3∠115.889°V.
Why do the voltages roughly match, but the phase angles do not? Do you think book made mistake?

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gneill
Mentor

Image Attached

## Homework Equations

Thevenin, Series, Parallel

## The Attempt at a Solution

j10(12-j34) / (j10+12-j34) = (340 + 120j) / (12/j24)

1.67 + j13.3 or 13.44∠82.4°

Now why can't I just use this equivalent resistance and multiply by the current source (22∠30°) to find the Thevenin Voltage? The result of doing this is 295.68∠112.8°V. Instead, the book uses Nodal Analysis to find VTH, which results in 295.3∠115.889°V.
Why do the voltages roughly match, but the phase angles do not? Do you think book made mistake?

Your analysis looks okay. It's quite possible for a text to have a typo or mistake. If the book presents all the steps of their solution, perhaps you can spot where their error has occurred.