High operational efficiency is achieved with transformer coupling because___________?
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Answer: B. resistance is low
Explanation
Transformer coupling achieves high electrical efficiency because transformers provide excellent impedance matching capabilities. The copper winding resistance inside well-designed audio transformers is kept exceptionally low to minimize losses. Minimal winding resistance ensures that most of the input signal power transfers successfully to the load. Impedance matching maximizes power transfer between amplifier output stages and low-resistance speaker loads. Transformers utilize electromagnetic induction to transform voltage and current levels without consuming active power. Core and copper losses represent the primary inefficiencies found within practical inductive coupling components.
Public address audio systems utilize transformer coupling to drive multiple remote loudspeakers over long lines. Radio frequency transmitters use impedance-matching transformers to transfer maximum power to broadcast antennas. High efficiency reduces internal heat generation, improving the long-term reliability of electronic equipment. Stepping up collector voltage alone does not guarantee high power transfer efficiency without proper impedance matching. None of the above is incorrect because low winding resistance is a primary technical reason for efficiency. Collector voltage stepping down is a secondary consequence rather than the primary driver of circuit efficiency.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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