|See also Coriolis force an imaginary force which an accelerated observer postulates so that he can use the equations appropriate to an inertial observer|
|inertial force (ĭ-nûr'shəl) Pronunciation Key
An apparent force that appears to affect bodies within a non-inertial frame, but is absent from the point of view of an inertial frame. Centrifugal forces and Coriolis forces, both observed in rotating systems, are inertial forces. Inertial forces are proportional to the body's mass. See also General Relativity.
any force invoked by an observer to maintain the validity of Isaac Newton's second law of motion in a reference frame that is rotating or otherwise accelerating at a constant rate. For specific inertial forces, see centrifugal force; Coriolis force; d'Alembert's principle.
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