Mass flow rate converter

A mass flow is a volume flow times a density, which is why engineers prefer it for gases and hot liquids whose volume changes with temperature and pressure: 1 l/s of water is 1 kg/s, but 1 m³/s of air is only 1.2 kg/s. Aircraft fuel is metered in kg/h – an Airbus A320 burns about 2,500 kg/h in cruise, a Boeing 747 some 10 t/h – and a car at motorway speed uses 5–6 kg/h. Steam boilers and process plants are rated in tonnes per hour, US industry in lb/h, and a mass flow in kg/s times an exhaust speed in m/s gives the thrust of a rocket engine in newtons.