Oilers/Plant Tenders (HHC) Civil Service Practice Exam

Disable ads (and more) with a membership for a one time $2.99 payment

Prepare for the Oilers/Plant Tenders Exam with our comprehensive quiz. Utilize flashcards and multiple choice questions with hints and explanations to excel in your civil service test. Start your preparation now!

Start Multiple Choice Practice Test
Start Flash Cards

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

Practice this question and more.

What unit is the vacuum reading on a compound pressure gauge usually measured in?

  1. Inches of mercury

  2. Millimeters of mercury

  3. Pascals

  4. Pounds per square inch

The correct answer is: Inches of mercury

The vacuum reading on a compound pressure gauge is typically measured in inches of mercury. This unit is used because it provides a convenient way to express both positive and negative pressures in practical applications, particularly in the fields of mechanics and engineering. The measurement in inches of mercury (inHg) indicates how many inches of mercury would exert the same pressure as the vacuum being measured. This reflects the atmospheric pressure standard where the weight of a column of mercury can be used to quantify pressures below atmospheric levels, hence the relevance in vacuum applications. While other units like millimeters of mercury (used in some international contexts) and pascals (the SI unit for pressure) are also valid for measuring pressure, inches of mercury is the most commonly used unit in the US, making it the preferred choice for many practical scenarios involving vacuum measurements. Pounds per square inch is primarily a measurement for gauging positive pressures and is less applicable in the context of vacuum.

More Questions Like This