How are mm, torr, psi, atm, and Pa related to each other?
http://en.wikipedia.org/wiki/Pressure#Units
The units mm, torr, psi, atm, and Pa are all used to measure pressure. Let's go through each unit and understand how they are related to each other:
1. Millimeter of Mercury (mmHg):
- This unit is commonly used in medicine and is based on the height of a column of mercury in a barometer.
- 1 mmHg is equivalent to 1 torr, as "torr" is a unit used to measure pressure based on the height of a mercury column.
2. Torr:
- The torr is another unit commonly used to measure pressure.
- 1 torr is equal to the pressure exerted by a 1 mmHg column of mercury.
- Therefore, 1 torr is also equal to 133.322 Pa (Pascal), which is the SI unit for pressure.
3. Pounds per Square Inch (psi):
- This unit is commonly used in engineering and industry, particularly in the United States.
- 1 psi is defined as the pressure resulting from a force of one pound-force applied to an area of one square inch.
- 1 psi is approximately equal to 6895 pascals.
4. Atmosphere (atm):
- The atmosphere is a unit commonly used in meteorology and for everyday atmospheric pressure.
- 1 atm is defined as the average atmospheric pressure at sea level on Earth, which is approximately equal to 101325 pascals.
- 1 atm is also approximately equal to 760 mmHg or 760 torr.
5. Pascal (Pa):
- The Pascal is the SI unit for pressure and is used in scientific and international contexts.
- 1 Pascal is defined as the pressure exerted by a force of 1 Newton on an area of 1 square meter.
In summary, mm, torr, psi, atm, and Pa are different units used to measure pressure. They are related to each other through conversion factors: 1 atm = 101325 Pa = 760 mmHg = 760 torr, and 1 torr = 133.322 Pa. These conversion factors can be used to convert between any of these pressure units.