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To convert from meter of water @ 4°C (mH2O) to torr (torr), use the following formula:
Let's convert 5 meter of water @ 4°C (mH2O) to torr (torr).
Using the formula:
Therefore, 5 meter of water @ 4°C (mH2O) is equal to torr (torr).
Here are some quick reference conversions from meter of water @ 4°C (mH2O) to torr (torr):
| meters of water @ 4°C | torr |
|---|---|
| 0.000001 mH2O | torr |
| 0.001 mH2O | torr |
| 0.1 mH2O | torr |
| 1 mH2O | torr |
| 2 mH2O | torr |
| 3 mH2O | torr |
| 4 mH2O | torr |
| 5 mH2O | torr |
| 6 mH2O | torr |
| 7 mH2O | torr |
| 8 mH2O | torr |
| 9 mH2O | torr |
| 10 mH2O | torr |
| 20 mH2O | torr |
| 30 mH2O | torr |
| 40 mH2O | torr |
| 50 mH2O | torr |
| 100 mH2O | torr |
| 1000 mH2O | torr |
| 10000 mH2O | torr |
For all Pressure converters, choose units using the From/To dropdowns above.
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.
A torr (Torr) is a unit of pressure.
It is primarily used to measure a vacuum, or pressures much lower than the air pressure we experience every day.
While the modern standard (SI) unit for pressure is the pascal (Pa), the torr is still widely used in many scientific and engineering fields.
For conversion, one torr is equal to about 133.32 pascals.
A much simpler way to think about it is in relation to our atmosphere: one standard atmosphere (atm) is defined as exactly 760 Torr.
The unit is named in honor of Evangelista Torricelli, the 17th-century Italian physicist who invented the mercury barometer.
Because of this, one torr was initially defined as being equal to one millimeter of mercury (mmHg).
This means 1 Torr is the pressure exerted by a column of mercury that is one millimeter high.
As mentioned, the torr's most convenient relationship is with the standard atmosphere (atm).
One standard atmosphere—the average air pressure at sea level—is set at exactly 760 Torr.
This straightforward, whole-number conversion makes the torr a popular choice for anyone working with fractions of atmospheric pressure.
The torr is the primary unit of measurement for high-vacuum and ultra-high-vacuum technology.
Because it is such a small unit (it takes 760 of them to equal one atmosphere), it is ideal for quantifying pressures far below normal air pressure.
You will find the torr used in many advanced scientific and industrial fields, including: