Mass vs Inertia: Is Inertia Necessary in Physics?

AI Thread Summary
The discussion questions the necessity of the term "inertia" in physics, suggesting it may be redundant given the clear definitions of mass and momentum. It highlights that "inertia" is often used in non-scientific contexts, such as sports commentary, leading to ambiguity. The argument posits that since physics texts do not use "inertia" in a standalone manner, its elimination could simplify understanding. The conversation emphasizes the importance of precise language in scientific discourse. Ultimately, the term "inertia" may not add value and could be replaced by more accurate terminology.
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Is there any difference between mass and inertia? Is the word "inertia" necessary, or could it be eliminated from physics books?
 
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Look in a physics text beyond the introductory level. You'll see mass, you'll see moment of inertia, but you'll never see "inertia" by itself. Inertia is a nice term used by sports announcers in describing what happens when an American football linesman meets an American football running back, or when describing why they think a football team that has won ten games straight will win again this weekend. Here's the problem: Does the announcer mean mass or momentum, or is he talking about something that has absolutely nothing to do with science?

Why use a term that's ambiguous when there are two perfectly good, unambiguous words that mean mass and momentum? (Hint: The words are "mass" and "momentum".)
 

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