This is a revision of a book currently in its fourth edition which deals with the modeling of physical systems. With this edition (as with prior editions) one of the key features is the extensive use of bond graphs to illustrate and model physical systems. Dynamic systems are taught either using bond graph or not - so the market for Karnopp's book is clearly defined. Bond graphs are a graphical breakdown of a system which illustrates the structure of the system focusing on the flow of information and energy. In this way engineers can better understand the overall system, the various components, and whether they are electrical, chemical, mechanical, etc. The book includes coverage of electromechanical transducers, mechanical systems in plane motion, and formulas for computing hydraulic compliances and for modeling acoustic systems. New chapters and sections are being added that cover the use of physical system models beyond simply predicting system performance - including automatic control, observers, parameter studies for system design, and concept testing. As with the previous editions there will be a solutions manual to accompany this edition.