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To convert from meter of water @ 4°C (mH2O) to millimeter of mercury (mmHg), use the following formula:
millimeter of mercury (mmHg)
= 9.80665 × 10.133322× meter of water @ 4°C (mH2O)
= 73.556127270818019532× meter of water @ 4°C (mH2O)
Let's convert 5 meter of water @ 4°C (mH2O) to millimeter of mercury (mmHg).
Using the formula:
5 × 73.556127270818019532 = 367.78063635409009766
Therefore, 5 meter of water @ 4°C (mH2O) is equal to 367.78063635409009766 millimeter of mercury (mmHg).
How many meters of water @ 4°c are in one millimeter of mercury? One millimeter of mercury (mmHg) contains 0.013595060494664334916 meters of water @ 4°C (mH2O) — the inverse of the factor above. Multiplying by 73.556127270818019532 takes you from meters of water @ 4°c to millimeters of mercury; multiplying by 0.013595060494664334916 brings you back.
Put in words: one meter of water @ 4°c equals 73.556127270818019532 millimeters of mercury, so the meter of water @ 4°c is the larger unit of this pair. Converting between them never changes the amount of pressure being measured — only the size of the unit you count it in.
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 millimeter of mercury (mmHg) is a manometric unit of pressure.
It was historically defined as the pressure generated by a column of mercury exactly one millimeter high.
Today, it is most famous as the unit used in medicine for measuring blood pressure. It is also commonly used in meteorology, aviation, and physics to measure atmospheric pressure or vacuum pressure.
The mmHg unit originates from the invention of the barometer by Evangelista Torricelli in 1643.
Torricelli's device measured atmospheric pressure by seeing how high it could support a column of mercury in a tube.
Standard atmospheric pressure was found to support a column approximately 760 mm high, which established 760 mmHg as a standard reference point.
The most well-known application of mmHg is in medicine.
Blood Pressure: Readings are given as two numbers: systolic pressure (when the heart beats) over diastolic pressure (when the heart rests), such as 120/80 mmHg. This is a critical vital sign for human health.
Meteorology: Used for reporting barometric (atmospheric) pressure, which helps in weather forecasting.
Physics & Engineering: Used for measuring vacuum pressures and other low-pressure systems where precision is needed.
While mmHg is common, other pressure units are standard in different fields. Here are the most common conversions:
Here are some quick reference conversions from meter of water @ 4°C (mH2O) to millimeter of mercury (mmHg):
| meters of water @ 4°C | millimeters of mercury |
|---|---|
| 0.000001 mH2O | 0.000073556127270818019532 mmHg |
| 0.001 mH2O | 0.073556127270818019532 mmHg |
| 0.1 mH2O | 7.3556127270818019532 mmHg |
| 1 mH2O | 73.556127270818019532 mmHg |
| 2 mH2O | 147.11225454163603906 mmHg |
| 3 mH2O | 220.6683818124540586 mmHg |
| 4 mH2O | 294.22450908327207813 mmHg |
| 5 mH2O | 367.78063635409009766 mmHg |
| 6 mH2O | 441.33676362490811719 mmHg |
| 7 mH2O | 514.89289089572613672 mmHg |
| 8 mH2O | 588.44901816654415626 mmHg |
| 9 mH2O | 662.00514543736217579 mmHg |
| 10 mH2O | 735.56127270818019532 mmHg |
| 20 mH2O | 1471.1225454163603906 mmHg |
| 30 mH2O | 2206.683818124540586 mmHg |
| 40 mH2O | 2942.2450908327207813 mmHg |
| 50 mH2O | 3677.8063635409009766 mmHg |
| 100 mH2O | 7355.6127270818019532 mmHg |
| 1000 mH2O | 73556.127270818019532 mmHg |
| 10000 mH2O | 735561.27270818019532 mmHg |
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