For closed systems with no external source or sink of energy, the first law of thermodynamics states that a system's energy is constant unless energy is transferred in or out by mechanical work or heat, and that no energy is lost in transfer. This means that it is impossible to create or destroy energy.
GROGAN. The Irish name Grogan is derived from the native Gaelic O'Gruagain Sept that was initially located in County Roscommon but which became widely dispersed. The name is derived from a Gaelic word meaning 'fierceness'. Grugan, Groggan, Groogan and O'Grogan are among the variants of this name.he Irish name Grogan is derived from the native Gaelic O'Gruagain Sept that was initially located in County Roscommon but which became widely dispersed.
Recorded in the spellings of Grauer, Grayer, Greer, Greir, Grier, and the patronymic Grierson, this is usually a surname of Scottish ancestry, but widely recorded in England.he first recorded spelling of the family name is shown to be that of Gilbert Grier, which was dated 1542, a witness at Dumfries Court, Scotland, during the reign of Queen Mary, known as Queen of Scots, 1543 - 1587.