# pascal, Pa (unit)
This page documents an [OPTIMADE](https://www.optimade.org/) [Unit Definition](https://schemas.optimade.org/#definitions). See [https://schemas.optimade.org/](https://schemas.optimade.org/) for more information.
**ID: [`https://schemas.optimade.org/defs/v1.2/units/si/1983/named/pascal`](https://schemas.optimade.org/defs/v1.2/units/si/1983/named/pascal.md)**
**Definition name:** `pascal`
**Unit name:** pascal
**Latin symbol:** Pa
**Display symbol:** Pa
**Description:** A derived SI unit for pressure and stress equal to kg·m⁻¹·s⁻² using the 1983 SI units.
"The International Committee will ask the General Conference to approve two special names: pascal (symbol Pa) for the SI unit of pressure (N/m²), [...]" [14th CGPM Meeting (1971)].
The pascal was defined at the 14th CGPM Meeting in 1971 and implicitly redefined via the redefinition of the metre at the 17th CGPM Meeting in 1983, resolution 1.
**Resources:**
- [Definition at the 14th CGPM Meeting (1971)](https://www.bipm.org/en/committees/cg/cgpm/14-1971)
- [Redefinition of the metre at the 17th CGPM meeting (1983), resolution 1](https://www.bipm.org/en/committees/cg/cgpm/17-1983/resolution-1)
- [Wikipedia article describing the unit](https://en.wikipedia.org/wiki/Pascal_(unit))
**Formats:** [[JSON](pascal.json)] [[MD](pascal.md)]
**JSON definition:**
``` json
{
"$id": "https://schemas.optimade.org/defs/v1.2/units/si/1983/named/pascal",
"$schema": "https://schemas.optimade.org/meta/v1.2/optimade/physical_unit_definition.json",
"title": "pascal",
"symbol": "Pa",
"display-symbol": "Pa",
"description": "A derived SI unit for pressure and stress equal to kg\u00b7m\u207b\u00b9\u00b7s\u207b\u00b2 using the 1983 SI units.\n\n\"The International Committee will ask the General Conference to approve two special names: pascal (symbol Pa) for the SI unit of pressure (N/m\u00b2), [...]\" [14th CGPM Meeting (1971)].\n\nThe pascal was defined at the 14th CGPM Meeting in 1971 and implicitly redefined via the redefinition of the metre at the 17th CGPM Meeting in 1983, resolution 1.",
"resources": [
{
"relation": "Definition at the 14th CGPM Meeting (1971)",
"resource-id": "https://www.bipm.org/en/committees/cg/cgpm/14-1971"
},
{
"relation": "Redefinition of the metre at the 17th CGPM meeting (1983), resolution 1",
"resource-id": "https://www.bipm.org/en/committees/cg/cgpm/17-1983/resolution-1"
},
{
"relation": "Wikipedia article describing the unit",
"resource-id": "https://en.wikipedia.org/wiki/Pascal_(unit)"
}
],
"defining-relation": {
"base-units": [
{
"symbol": "kg",
"id": "https://schemas.optimade.org/defs/v1.2/units/si/1960/base/kilogram"
},
{
"symbol": "m",
"id": "https://schemas.optimade.org/defs/v1.2/units/si/1983/base/metre"
},
{
"symbol": "s",
"id": "https://schemas.optimade.org/defs/v1.2/units/si/1967/base/second"
}
],
"base-units-expression": "kg*m^-1*s^-2"
},
"standard": {
"name": "si",
"year": 1983,
"category": "named",
"symbol": "Pa"
},
"x-optimade-definition": {
"label": "pascal_si_1983_named",
"kind": "unit",
"format": "1.2",
"version": "1.2.0",
"name": "pascal"
}
}
```