- A manometer is a U-shape tube filled with some liquid (usually mercury).
- Manometer is a device used to measure gas pressure in a container.
- The pressure of the gas is equal to the sum of the atmospheric pressure and pressure due to the column of liquid.
Pgas = Patm + Pliquid
Note:There are a few points we need to know when using a manometer
- Difference in gas pressure at difference level can be ignored.
- Pressure on the surface of liquid is equal to the gas pressure in contact.
- Pressure that cause by liquid = hρg.
- For a given liquid, the pressures at any point of the same level are the same.
- For different liquid with different density, pressure at two different level will be different.