Pascal (unit)

Pascal (symbol: Pa) is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus, and ultimate tensile strength. The unit, named after the French mathematician, physicist, and inventor Blaise Pascal, is defined as one newton per square metre.

Definition

One pascal is defined as the pressure of one newton per square metre. Mathematically, it is expressed as:

1 Pa = 1 N/m²

History

The unit is named after Blaise Pascal, who made significant contributions to the understanding of fluid mechanics and hydrostatics. The pascal was adopted as the SI unit of pressure in 1971.

Applications

The pascal is widely used in various fields, including meteorology, engineering, and material science. In meteorology, atmospheric pressure is often measured in hectopascals (hPa), where 1 hPa = 100 Pa. In engineering, the pascal is used to measure stress and Young's modulus.

Common Multiples

Due to the small size of the pascal, it is often expressed in multiples:

• 1 kilopascal (kPa) = 1,000 Pa
• 1 megapascal (MPa) = 1,000,000 Pa
• 1 gigapascal (GPa) = 1,000,000,000 Pa

Related Units

Other units of pressure include the bar, the atmosphere, and the torr. The pascal is related to these units as follows:

• 1 bar = 100,000 Pa
• 1 atmosphere = 101,325 Pa
• 1 torr ≈ 133.322 Pa

See Also

• Pressure
• Stress (mechanics)
• Young's modulus
• Ultimate tensile strength
• Blaise Pascal
• SI derived unit
• Newton (unit)