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Glite Dictionary
inertial mass

inertial mass

1 8.6
A measure of how hard it is to change an object's motion when a force pushes it
  • noun
  • /ɪˈnɜrʃəl mæs/
  • Specialized
translation icon : masa inercial
  • At the heart of gravitational theory is a concept called the Einstein equivalence principle, which modernizes Newton's postulate of the equivalence of gravitational and inertial mass.
  • gravitational and inertial mass

This little M is the mass of our object, and I'm calling it the inertial mass because it's the mass that plays the role in this equation.

Examples

  • An object's inertial mass determines how quickly it can accelerate when a force is applied.

  • If you could reduce the inertial mass of a vehicle, you could get far more propulsion from your fuel.

    Academic text (2000)

  • It's sometimes referred to as inertial mass for this reason.

  • And so the kind of mass that I defined last time is the inertial mass, how much it resists being pushed.

  • A car with a smaller inertial mass will accelerate faster than a heavier vehicle when both are pushed with the same force.

  • To understand motion, one must consider an object's inertial mass, which influences how it reacts to applied forces.

Synonyms

mass
vsinertial mass
  • Specialized
190 4.1

The amount of matter in an object that makes it heavy and hard to move

is only about resistance to acceleration under applied forces not weight in gravity

Surface Forms

inertial mass singular
inertial masses plural

Morphology

inertial + mass

The compound is transparently built from 'inertial' (pertaining to inertia) + 'mass' (amount of matter resisting acceleration), so its meaning — the mass relevant to an object's inertia/response to force — follows directly from the constituents. This is a compositional, technical label rather than an idiom, and the same modifier+noun logic occurs cross-linguistically, so a learner who knows both words should grasp the term.

Etymology

Inertial mass combines inertial, a word from the idea of 'hard to change motion', and mass, the amount of stuff, so imagine pushing an empty shopping cart and a full one, and the full cart is much harder to start moving. So inertial mass means 'how hard an object is to speed up or slow down when you push it'.