Commonly Used Words. Arranged alphabetically, these sections include spelling, usage, punctuation and capitalization notes for specific words and phrases commonly used in the CSU. An entry without an explanation is simply to indicate the correct spelling of a word or words. A B-C D-F G-M N-S T-Z.
Noun. 1. Newton's first law of motion-a body remains at rest or in motion with a constant velocity unless acted upon by an external force. first law of motion, Newton's first law. law of motion, Newton's law, Newton's law of motion-one of three basic laws of classical mechanics.
Newton's first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force. This is normally taken as the definition of inertia.