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Sarkari MCQs Government Exam Question Bank
Question no. 13298

Ultra-low pressures are denoted in microns (μ), equivalent to ____________ mm of Hg column (absolute) at 0°C?

Select your answer for: Ultra-low pressures are denoted in microns (μ), equivalent to ____________ mm of Hg column (absolute) at 0°C?
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Answer: B. 0.001

Explanation

One micron of mercury pressure represents an ultra-low pressure measurement scale in vacuum technology. By definition, one micron equals one thousandth of a millimeter of mercury column absolute at zero degrees. This precise conversion factor relates micro-pressure units to standard manometer height measurements. Vacuum measurements often utilize specialized units like microns to express extremely low absolute pressures. One millimeter of mercury is equivalent to one torr in traditional vacuum engineering standards. Standard temperature conditions are referenced to ensure accurate calibration of low-pressure gauges.

High-vacuum coating chambers and semiconductor manufacturing equipment require precise micron-level monitoring. Leak detection in industrial vacuum systems relies on accurate ultra-low pressure instrumentation. Scientific research facilities use specialized vacuum gauges to maintain controlled cryogenic environments. Option A represents zero point zero zero zero one, which fails the standard micron conversion ratio. Option C represents ten microns rather than the specific definition of a single micron unit. Option D represents one hundred microns, which is significantly higher than the correct conversion.

Subject
Engineering
Category
Chemical Engineering
Topic
—
Difficulty
medium

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