inertial mass

noun Physics.

the mass of a body as determined by the second law of motion from the acceleration of the body when it is subjected to a force that is not due to gravity.
the measure of the property of inertia.Compare Eötvös experiment, inertia(def 2a), gravitational mass.

Nearby words

  1. inertial,
  2. inertial force,
  3. inertial frame,
  4. inertial fusion,
  5. inertial guidance,
  6. inertial observer,
  7. inertial platform,
  8. inertial system,
  9. inertial upper stage,
  10. inertness Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for inertial mass

inertial mass


the mass of a body as determined by its momentum, as opposed to gravitational mass. The acceleration of a falling body is inversely proportional to its inertial mass but directly proportional to its gravitational mass: as all falling bodies have the same constant acceleration the two types of mass must be equal

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