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To convert from pascal (Pa) to meter of water @ 4°C (mH2O), use the following formula:
Let's convert 5 pascal (Pa) to meter of water @ 4°C (mH2O).
Using the formula:
Therefore, 5 pascal (Pa) is equal to meter of water @ 4°C (mH2O).
Here are some quick reference conversions from pascal (Pa) to meter of water @ 4°C (mH2O):
| pascals | meters of water @ 4°C |
|---|---|
| 0.000001 Pa | mH2O |
| 0.001 Pa | mH2O |
| 0.1 Pa | mH2O |
| 1 Pa | mH2O |
| 2 Pa | mH2O |
| 3 Pa | mH2O |
| 4 Pa | mH2O |
| 5 Pa | mH2O |
| 6 Pa | mH2O |
| 7 Pa | mH2O |
| 8 Pa | mH2O |
| 9 Pa | mH2O |
| 10 Pa | mH2O |
| 20 Pa | mH2O |
| 30 Pa | mH2O |
| 40 Pa | mH2O |
| 50 Pa | mH2O |
| 100 Pa | mH2O |
| 1000 Pa | mH2O |
| 10000 Pa | mH2O |
For all Pressure converters, choose units using the From/To dropdowns above.
A pascal (Pa) is the standard unit of pressure in the International System of Units (SI). It is a derived unit, meaning other base units define it.
The primary pascal definition is one newton of force applied over an area of one square meter (1 Pa = 1 N/m2).
Because a single pascal represents a very small amount of pressure, it is most often seen in multiples.
The most common multiples are the kilopascal (kPa), equal to 1,000 pascals, and the megapascal (MPa), equal to 1,000,000 pascals.
These units are widely used in fields from weather forecasting to material science.
The pascal (Pa) unit is named in honor of Blaise Pascal, a key 17th-century French mathematician, physicist, and inventor.
His groundbreaking work on how fluids behave under pressure (known as hydrodynamics and hydrostatics) and his formulation of Pascal's Law were essential to our modern understanding of pressure.
To understand just how small a single pascal is, here are two real-world examples:
This shows why, for most everyday measurements (like tire pressure or weather), the larger kilopascal (kPa) is much more practical.
A meter of water @ 4°C (mH2O) is a metric unit used to measure pressure.
It is precisely defined as 9.80665 kilopascals (kPa).
The specific temperature of 4°C (39.2°F) is key because this is the point where pure water is at its heaviest or most dense (approximately 999.972 kg/m3).
Using this temperature provides a stable and reliable standard for defining pressure.
This precision is essential in scientific and engineering fields like hydraulics and fluid mechanics, ensuring that measurements of pressure head are consistent and accurate across different applications and locations.
The unit "meter of water" (mH2O) is frequently used in civil engineering, hydrology, and irrigation to measure water levels and pressure.
It provides an intuitive way to express the pressure exerted by a column of water, such as the water level in a reservoir, dam, or groundwater well. This measurement is sometimes referred to as the 'piezometric head'.
It is also commonly used to specify the performance of pumps, indicating the height to which a pump can lift water.
For practical use, it's often helpful to know how mH2O converts to other common pressure units.
One mH2O is equal to:
These conversion factors allow engineers and scientists to easily translate pressure specifications between different international and imperial systems.