Four 8 Ω speakers in parallel connect to an audio amplifier supplying 12 V maximum. What power must the amplifier deliver_____________?
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Answer: D. 72 W
Explanation
Four eight ohm speakers connected in parallel result in an equivalent combined resistance of two ohms. Electrical power equals the square of the voltage divided by the equivalent circuit resistance. Squaring twelve volts and dividing by two ohms yields a total power delivery of seventy two watts. Parallel speaker wiring reduces total impedance while distributing amplifier power among drivers. Audio amplifiers are rated for specific minimum load impedances to prevent internal overheating. Power calculations use root mean square voltage values in standard AC audio engineering formulas.
Sound system installers must calculate parallel impedances to match amplifiers safely and efficiently. Exceeding amplifier power delivery ratings can damage voice coils in connected audio speakers. Proper impedance matching ensures maximum transfer of audio power from amplifier to speakers. Option A calculates an incorrect power value by misapplying the parallel resistance formula. Option B underestimates power delivery significantly by confusing voltage and resistance terms. Option C calculates power using an incorrect equivalent resistance value for the speaker network.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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