The pascal
N/m² is called pascal.
A new unit
Force is measured in newton (N). Area is measured in square metre (m²). Pressure is force divided by area.
What should the unit of pressure be?
What this lesson covers
The idea
The SI unit of pressure is newton per square metre (N/m²), called the pascal (Pa); air pressure is also expressed in millibar or hectopascal, each equal to 100 Pa.
A new unit
Force is measured in newton (N). Area is measured in square metre (m²). Pressure is force divided by area.
What should the unit of pressure be?
- Newton per square metre
- Kilogram
- Metre
Build the unit
Press Next step to see where the unit comes from.
Pascal
A force of 1 N pressing on 1 m² gives a pressure of 1 N/m², which is 1 pascal. Air pressure is a larger number in pascal, so mb or hPa is handy.
SI unit of pressure: N/m² = pascal (Pa). 1 mb = 1 hPa = 100 Pa.
- Unit | Equal to
- 1 pascal (Pa) | 1 N/m²
- 1 millibar (mb) | 100 Pa
- 1 hectopascal (hPa) | 100 Pa
Notes
The SI unit of pressure is N/m² = pascal (Pa). 1 mb = 1 hPa = 100 Pa.
Check yourself
The SI unit of pressure is …
1 hectopascal (hPa) is equal to how many pascal?
Answer: 100 Pa
1 hPa = 100 Pa, and 1 mb = 100 Pa too.
A force of 500 N acts on an area of 5 m². What is the pressure in pascal?
Answer: 100 Pa
500 N ÷ 5 m² = 100 N/m² = 100 Pa.
Which of these is the same as 1 millibar?
- kg. Kilogram is the unit of mass, not pressure.
- N/m², called pascal — correct. Yes!
- m². Square metre is the unit of area. Pressure is force per area.
- 1 Pa. A millibar is 100 times bigger than a pascal.
- 1 N. Newton is the unit of force. Pressure is measured in pascal.
- 100 Pa — correct. Yes!