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To convert from bar (bar) to meter of water @ 4°C (mH2O), use the following formula:
Let's convert 5 bar (bar) to meter of water @ 4°C (mH2O).
Using the formula:
Therefore, 5 bar (bar) is equal to meter of water @ 4°C (mH2O).
Here are some quick reference conversions from bar (bar) to meter of water @ 4°C (mH2O):
| bar | meters of water @ 4°C |
|---|---|
| 0.000001 bar | mH2O |
| 0.001 bar | mH2O |
| 0.1 bar | mH2O |
| 1 bar | mH2O |
| 2 bar | mH2O |
| 3 bar | mH2O |
| 4 bar | mH2O |
| 5 bar | mH2O |
| 6 bar | mH2O |
| 7 bar | mH2O |
| 8 bar | mH2O |
| 9 bar | mH2O |
| 10 bar | mH2O |
| 20 bar | mH2O |
| 30 bar | mH2O |
| 40 bar | mH2O |
| 50 bar | mH2O |
| 100 bar | mH2O |
| 1000 bar | mH2O |
| 10000 bar | mH2O |
For all Pressure converters, choose units using the From/To dropdowns above.
The bar is a metric unit of pressure.
It is defined as exactly 100 kilopascals (kPa), or 100,000 Pascals (Pa).
Although it is not an official part of the International System of Units (SI), it is widely accepted for use with the SI. The bar is a popular unit for measuring pressure because it is very close to the average atmospheric pressure on Earth at sea level.
The term "bar" comes from the Greek word βάρος (baros), which means "weight."
The unit was introduced by British meteorologist William Napier Shaw in 1909. It is still widely used in meteorology, oceanography, and engineering.
A common point of confusion is the difference between a bar and a standard atmosphere (atm).
While they are very close in value, they are not the same:
This means 1 bar is approximately equal to 0.987 atm. Because it's so close to atmospheric pressure and is a round number (100 kPa), the bar is a very convenient unit for many applications.
The bar is a versatile unit used to measure pressure in many industrial and everyday contexts.
Common examples include:
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.