Using the illustrated vacuum equivalents chart as a reference, which of the following vacuums listed represents the deepest vacuum? See illustration GS-RA-57.
β’ Gauge vs absolute pressure on the chart (Inches Mercury Gauge vs Inches Mercury Absolute / Torr / Micron). β’ How the chart shows that a deeper vacuum = lower absolute pressure (Torr, mm Hg, or microns). β’ Unit relationships: 1 inch Hg β 25.4 mm Hg, and 1 mm Hg = 1000 microns.
β’ On the chart, which column(s) should you use to fairly compare all four choices, since some are in inches, some in mm, and some in microns? β’ After converting everything to the same type of value (for example, mm Hg absolute), which option gives the smallest absolute pressure, and therefore the deepest vacuum? β’ Where on the chart (top or bottom) do you find the deeper vacuums, and which of the listed values appears closest to that region when converted?:
β’ Be sure you are comparing absolute pressures, not gauge readings, when judging vacuum depth. β’ Convert or read off each choice so they are all in the same unit (all in mm Hg abs or all in microns). β’ Verify from the chart that the deepest vacuum corresponds to the highest % vacuum / lowest Torr or micron value, then see which choice matches that.
No comments yet
Be the first to share your thoughts!