Pressure measurement because atmospheric pressure is always changing and the reference in this case is fixed at 1 bar. To produce an absolute pressure sensor, the manufacturer seals a high vacuum behind the sensing diaphragm. If the process-pressure connection of an absolute-pressure transmitter is open to the air, it will read the actual barometric pressure. The SI unit for pressure is the pascal (Pa), equal to one newton per square metre (N·m or kg·m·s). This special name for the unit was added in 1971; before that, pressure in SI was expressed in units such as N·m. When indicated, the zero reference is
Kos (unit) Kos (unit) The kos (Sanskrit: कोस), also spelled Kosh, Krosh, krosha and Koss, is an ancient Indian subcontinental "Arthashastra standard unit" of distance, since at least 4 BCE. A kos is about 3.00 km or 1.91 miles. The ""Arthashastra: Chapter XX. Measurement of space and time"", authored in 4th century BCE by Chanakya (Vishnugupta Kauṭilya), sets this standard breakup of Indian units of length: Kos may also refer to roughly 1.8 km (1 mile) or 3.2 km (2 miles). "Arthashastra Standard unit" of Kos or krosh is equal to 3075 metres in SI units and 1.91 miles in Imperial units.