Engineering Board Exam Reviewer · Circuit Theorems in AC Analysis · easy
A source has an internal impedance of Zs=40+j30, . For maximum average power transfer, the load impedance must be
- 40+j30,
- 40-j30,
- 50,
- 40,
Answer
B. 40-j30,
Solution
Maximum power transfer to a complex load requires ZL=Zs*, the complex conjugate of the source impedance: 40-j30, . The reactances cancel and the resistances match.
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