How is the internal temperature of an industrial furnace usually measured ?
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Answer: A. Optical pyrometer
Explanation
Optical pyrometers measure high internal furnace temperatures without physical contact. They compare the optical brightness of radiation emitted by the hot target to a calibrated filament. This non-contact method prevents sensor damage from extreme internal furnace environments. Pyrometers are specialized instruments designed to measure high radiant temperatures. Physical thermometers like mercury devices would vaporize instantly inside industrial furnaces. Radiation pyrometry relies on the predictable relationship between temperature and emitted light.
Metallurgists use optical pyrometers to monitor molten metal temperatures in steel plants. Accurate temperature measurement ensures proper alloy composition and casting quality. Non-contact sensors allow safe remote monitoring of high temperature industrial processes. Mercury thermometers boil and rupture at temperatures far below industrial furnace levels. Alcohol thermometers have very low boiling points, making them useless for high heat. The correct answer option is explicitly provided, making the any of the above choice false.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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