Which of the following is not a unit of pressure?

1:45 PM    Measurement Units , Physics , Pressure   

Q. Which of the following is not a unit of pressure?

1. Pascal
2. Torr
3. Dynes
4. Atm

Answer: Dynes

Pascal, Torr and Atm are the units of pressure while Dyne is a unit of force

The dyne (symbol dyn) is a derived unit of force specified in the centimeter–gram–second (CGS) system of units, a predecessor of the modern SI.

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Q. Which of the following is not the unit of pressure?

1. kg/cm²
2. Bar
3. Atmosphere
4. Newton

Answer: Newton
kg/cm², Bar and Atmosphere are the units of pressure whereas Newton is a unit of force.

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Q. Which of the following is not a unit of pressure?

1. Parsec
2. Kilo-pascal
3. Bar
4. Newton/meter ²

Answer: Parsec
Kilo-pascal, Bar and Newton/meter ² are the units of pressure whereas Parsec is a unit of length.

A parsec is a unit of distance used in astronomy. It is the distance that light travels in 3.26 years, or just under 31 trillion kilometers (about 19 trillion miles). This is from the definition: a parsec is the distance from the Sun to an object which has a parallax angle of one arcsecond.

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Q. Which of the following is not a unit of pressure?

1. Newton/m ²
2. Torr
3. Ata, bar or pascal
4. Parsec

Answer: Parsec
Newton/m ² , Torr, Ata, bar and Pascal are the units of pressure while Parsec is a unit of distance.

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Units of Measurement provide standards so that the numbers from our measurements refer to the same thing. Measurement is a process that uses numbers to describe a physical quantity. We can measure how big things are, how warm they are, how heavy they are, and lots of other features as well.

Pressure means how much something is pushing on something else. It is expressed as force per unit area: P=F/A

To measure the amount of pressure people use these units:

• Pounds per square inch (psi, PSI, lb/in², lb/sq in). Normal atmospheric pressure is 14.7 psi, which means that a column of air one square inch in area rising from the Earth's atmosphere to space weighs 14.7 pounds (6.7 kg).
• Atmosphere (atm). Normal atmospheric pressure is called 1 atmosphere. 1 atm = 14.7 psi = 760 torr.
• Torr. This is called the Torr because it is based on the original Torricelli barometer design. One atmosphere of pressure will push the column of mercury (Hg) in a mercury barometer to a height of 760 millimeters. A pressure that causes the Hg column to rise 1 millimeter is called a torr. 1 atm = 760 torr = 14.7 psi.
• Bar. The bar is almost the same as the atmosphere unit. One bar = 750.062 torr = 0.9869 atm = 100,000 Pa.
• Millibar - mb or mbar. There are 1,000 millibar in one bar. This unit is used by meteorologists who find it easier to refer to atmospheric pressures without using decimals. One millibar = 0.001 bar = 0.750 torr = 100 Pa.
• Pascal (Pa) is the SI unit of pressure. It was named after the French physicist Blaise Pascal. 1 pascal = a force of 1 newton per square meter (1 newton = the force needed to accelerate 1 kilogram one meter per second per second = 1 kg • m/s²; this is actually quite logical for physicists and engineers, honest). 1 pascal = 10 dyne/cm² = 0.01 mbar. 1 atm = 101,325 pascals = 760 mmHg = 760 torr = 14.7 psi.
  • Kilopascal - kPa. The prefix "kilo" means "1,000", so one kilopascal = 1,000 Pa. Therefore, 101.325 kPa = 1 atm = 760 torr and 100 kPa = 1 bar = 750 torr.
  • Megapascal - MPa. The prefix "mega" means "1,000,000", so one megapascal = 1,000 kPa = 1,000,000 Pa. Pressures in the megapascal range are common in high-pressure air compressors and hydraulic systems, where high-pressure liquids are used to do useful work.

Pressure is directly proportionate to force and inversely proportionate to area.