Some effects are proportional to the quantity while some effects are proportional to the rate of change, or the rate of change of the rate of change, of the quantity. Many other quantities and effects are measured. Viscosity is measured by its damping of a vibrating reed. Sonar and radar may be augmented by transponders onthe measured objects. Medical imaging systems using several types of radiation show details of the body's interior.
Reagent color indicates chemical quantities.
Other essays in this series deal with motors and generators, electro-mechanical actuators, amplifiers, and other devices. It is included by McGraw-Hill in their Electronic Engineers' Book Club. This is thebook which introduced and explains Minimum Constraint Design. How to be a successful engineer. Consulting electro-mechanical engineering.