Work (thermodynamics) of the energy went out as heat, and how much as work. This can be summarized by saying that heat and work are not state functions of the system. This is in contrast to classical mechanics, where net work exerted by a particle is a state function. Pressure–volume work (or "PV" work) occurs when the volume of a system changes. "PV" work is often measured in units of litre-atmospheres where = . However, the litre-atmosphere is not a recognised unit in the SI system of units, which measures P in Pascal (Pa), V in m, and PV in Joule (J),
Department of Scientific and Industrial Research (United Kingdom) purposes. Large areas of research were the responsibility of other bodies - aviation, atomic energy, agriculture, health and medicine, meteorology - though it might undertake specific investigation on behalf of the responsible departments. The department encouraged and supported scientific research in universities and other institutions by means of grants for special research projects, research fellowships, studentships, grants to research associations and research contracts. The department absorbed or created a number of research organisations, which included large laboratories for special fields of work. Existing institutions for which it assumed responsibility were the National Physical Laboratory from the Royal Society in 1918,