Torque the vector cross product, p is the particle's linear momentum, and r is the displacement vector from the origin (the origin is assumed to be a fixed location anywhere in space). The time-derivative of this is: This result can easily be proven by splitting the vectors into components and applying the product rule. Now using the definition of force formula_17 (whether or not mass is constant) and the definition of velocity formula_18 The cross product of momentum formula_20 with its associated velocity formula_21 is zero because velocity and momentum are parallel, so the second term vanishes. By definition, torque τ
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