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Description
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Pressure (or stress) has the dimension mass per length time squared. The SI unit of pressure is the pascal, which is defined as a newton per square meter, or a kilogram per meter second squared.
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Maple knows the units of pressure listed in the following table.
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Name
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Symbols
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Context
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Alternate Spellings
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Prefixes
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bar
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bar
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SI *
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bars
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SI
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atmosphere
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atm @, atmos@
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standard *
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atmospheres
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at @
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technical
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barye
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standard *
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baryes
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SI
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pieze
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pz
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standard *
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piezes
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SI
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torr
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Torr
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standard *
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torrs
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SI
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vac
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standard *
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vacs
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SI
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pound_per_square_inch
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psi
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standard *
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pounds_per_square_inch
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meter_mercury
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mHg
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standard *
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meters_mercury, metre_mercury, metres_mercury
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SI
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`0degC`
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SI
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foot_mercury
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ftHg
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standard *
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feet_mercury
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`32degF`
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`60degF`
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inch_mercury
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inHg
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standard *
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inches_mercury
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`32degF`
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`60degF`
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meter_water
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mH2O
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standard *
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meters_water, metre_water, metres_water
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SI
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`4degC`
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SI
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foot_water
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ftH2O
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standard *
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feet_water
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`39.2degF`
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inch_water
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inH2O
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standard *
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inches_water
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`39.2degF`
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kipf_per_square_inch
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ksi
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standard
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pascal
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Pa
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SI
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pascals
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planck_pressure
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planck *
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planck_pressures
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An asterisk ( * ) indicates the default context, an at sign (@) indicates an abbreviation, and under the prefixes column, SI indicates that the unit takes all SI prefixes, IEC indicates that the unit takes IEC prefixes, and SI+ and SI- indicate that the unit takes only positive and negative SI prefixes, respectively. Refer to a unit in the Units package by indexing the name or symbol with the context, for example, pascal[SI] or mmHg[standard]; by using an abbreviation, for example, at; or, if the context is indicated as the default, by using only the unit name or symbol, for example, pascal or mmHg.
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The units of pressure are defined as follows.
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A bar is defined as pascals.
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A standard atmosphere is defined as pascals.
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A technical atmosphere is defined as a kilogramforce per square centimeter, that is, pascals.
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A barye is defined as a dyne per square centimeter.
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A pieze is defined as a sthene per square meter.
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A torr is defined as standard atmosphere.
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A vac is defined as a millibar.
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A pound per square inch is defined as a poundforce per inch squared.
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A planck pressure is defined as a planck mass per planck length per planck time squared.
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Mercury
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The meter, foot, and inch of mercury are the pressures exerted by columns of mercury meter, foot, and inch in height, respectively.
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A standard meter of mercury is defined as atmospheres.
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A 0 degree Celsius meter of mercury is defined as approximately pascals.
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A standard foot of mercury is defined as standard meter of mercury.
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A 32 degree Fahrenheit foot of mercury is defined as approximately pascals.
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A 60 degree Fahrenheit foot of mercury is defined as approximately pascals.
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A standard inch of mercury is defined as standard meter of mercury.
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A 32 degree Fahrenheit inch of mercury is defined as approximately pascals.
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A 60 degree Fahrenheit inch of mercury is defined as approximately pascals.
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Water
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The meter, foot, and inch of water are the pressures exerted by columns of water meter, foot, and inch in height, respectively.
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A standard meter of water is defined as the pressure exerted by kilograms per square meter assuming standard acceleration of free fall.
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A 4 degrees Celsius meter of water is defined as approximately pascals.
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A standard foot of water is defined as standard meter of water.
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A 39.2 degree Fahrenheit foot of water is defined as approximately pascals.
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A standard inch of water is defined as standard meter of water.
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A 39.2 degree Fahrenheit inch of water is defined as approximately pascals.
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Examples
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