Question 542General Subjects - Assistant Engineer70% to pass
Which of the listed temperature sensors consists of finely coiled wire, such as platinum, where the resistance varies directly with temperature?
AI Explanation
The correct answer is C) Resistance temperature detector (RTD).
An RTD consists of a coil of finely wound wire, often made of platinum, whose electrical resistance changes in direct proportion to changes in temperature. This direct relationship between resistance and temperature is what makes the RTD the correct choice among the provided options.
The other options are not correct because: A) a thermistor is a semiconductor device whose resistance changes with temperature, B) a bimetallic device relies on the differential expansion of two metals to indicate temperature, and D) a thermocouple generates a small voltage proportional to temperature, rather than using resistance.
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