Moment of inertia is diagonal and torques around the axes act independently of each other. When a body is free to rotate around an axis, torque must be applied to change its angular momentum. The amount of torque needed to cause any given angular acceleration (the rate of change in angular velocity) is proportional to the moment of inertia of the body. Moment of inertia may be expressed in units of kilogram meter squared (kg·m) in SI units and pound-foot-second squared (lbf·ft·s) in imperial or US units. Moment of inertia plays the role in rotational kinetics that mass (inertia) plays in linear kinetics
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