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.
Origins of the Clan One of the most powerful of the Border families, the name was derived from the Scots who invaded Dalriada (Argyll) from Ireland and the surname is found in all parts of Scotland. However in the Borders, an area that was never fully Gaelic speaking, it may have meant a Scottish Gaelic speaker.lan Grierson is a lowland Scottish clan. The surname Grierson is a patronymic form of the medieval Scottish personal name Grier which is a form of the personal name Gregory. It has been speculated by some that they may descend from the same line as Clan Gregor, however this is refuted by others.