Derivation of the Navier–Stokes equations equation), three important concepts may be concisely written: conservation of mass, conservation of momentum, and conservation of energy. Validity is retained if formula_5 is a vector, in which case the vector-vector product in the second term will be a dyad. A general momentum equation is obtained when the conservation relation is applied to momentum. If the intensive property formula_5; considered is the mass flux (also "momentum density"), i.e. the product of mass density and flow velocity formula_17, by substitution in the general continuum equation: where formula_19 is a dyad, a special case of tensor product, which results in a second
The Nature and Origins of Mass Opinion poorly informed, psychologically driven, and "mass-mediated" public opinion may be, it is capable of recognizing and focusing on its own conception of what matters. The Nature and Origins of Mass Opinion The Nature and Origins of Mass Opinion is a 1992 non-fiction book by political scientist John Zaller that examines the processes by which individuals form and express political opinions and the implications this has for public opinion research. The book has been called "the single most important book on public opinion since V. O. Key's 1961 classic, "Public Opinion and American Democracy"." Zaller argues that public opinion is heavily