inertial mass

American  

noun

Physics.

1. 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.

2. the measure of the property of inertia.

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inertial mass British  

noun

1. 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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Compare meaning

How does inertial-mass compare to similar and commonly confused words? Explore the most common comparisons:

• inertial mass vs. gravitational mass

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Example Sentences

See Examples For:

inertial mass

It later became central to Albert Einstein's theory of gravity through the equivalence principle, which connects gravitational mass with inertial mass.

From Science Daily ● Sep. 18, 2026

This inertial mass of an object is a measure of how difficult it is to alter the uniform motion of the object by an external force.

From Textbooks ● Aug. 12, 2015

The strong equivalence principle states that gravitational and inertial mass remain equal even when such self-gravitation is included.

From Science Magazine ● Mar. 5, 2015

I just want to get the script and say, 'Here's what I said about gravitational mass and inertial mass, or about Einstein's general theory of relativity or about entropy.

From The Guardian ● Mar. 24, 2011

He wondered how much damage one could do with a nearly weightless stone, then remembered that inertial mass was unaffected by gravitational fields, or the lack of them.

From The Dueling Machine by Ben Bova

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