Convert Pressure from meters of water @ 4°C to torr (mH₂O to torr)

meter of water @ 4°C to torr Conversion Formula

Example

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 367.77962003454231434 torr (torr).

How many meters of water @ 4°c are in one torr? One torr (torr) contains 0.013595098063156391997 meters of water @ 4°C (mH₂O) — the inverse of the factor above. Multiplying by 73.555924006908462867 takes you from meters of water @ 4°c to torr; multiplying by 0.013595098063156391997 brings you back.

Put in words: one meter of water @ 4°c equals 73.555924006908462867 torr, 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.

What is a meter of water @ 4°C (mH₂O)?

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 Significance of 4°C in Water Pressure

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.

Practical Uses in Engineering and Hydrology

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.

Conversion to Other Common Pressure Units

For practical use, it's often helpful to know how mH₂O converts to other common pressure units.

One mH₂O is equal to:

• 9.80665 kilopascals (kPa)
• 9806.65 Pascals (Pa)
• 0.098 bar (approximately)
• 1.422 pounds per square inch (psi) (approximately)

These conversion factors allow engineers and scientists to easily translate pressure specifications between different international and imperial systems.

What Is a Torr?

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.

Where Did the Torr Come From?

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.

Torr vs. Atmosphere (atm)

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.

Where Is the Torr Used Today?

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:

• Semiconductor manufacturing
• Thin-film deposition (like adding anti-reflective coatings to glasses)
• Mass spectrometry
• Particle accelerators
• Vacuum furnaces

meter of water @ 4°C to torr Conversion Table

Here are some quick reference conversions from meter of water @ 4°C (mH₂O) to torr (torr):