-as of [24 AUGUST 2025]-
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“A [BODY] REMAINS AT [REST] (OR IN [MOTION] AT A CONSTANT [SPEED] IN A [STRAIGHT LINE]) UNLESS IT IS ACTED UPON BY A [FORCE]”
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Oh, yes.
Translating them into special relativity is an excellent exercise.
It’s not terribly complicated, either.
Newton’s first law:
Typically this law is written as “Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.”
Completely unchanged in special relativity.
In many ways, Newton’s first law is simply the principle of relativity itself, and so naturally survives without any changes
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Translated from Latin, Newton’s first law reads,
Every object perseveres in its state of rest, or of uniform motion in a right line, unless it is compelled to change that state by forces impressed thereon
Newton’s first law expresses the principle of inertia:
the natural behavior of a body is to move in a straight line at constant speed.
A body’s motion preserves the status quo, but external forces can perturb this.
The modern understanding of Newton’s first law is that no inertial observer is privileged over any other.
The concept of an inertial observer makes quantitative the everyday idea of feeling no effects of motion.
For example, a person standing on the ground watching a train go past is an inertial observer.
If the observer on the ground sees the train moving smoothly in a straight line at a constant speed, then a passenger sitting on the train will also be an inertial observer:
the train passenger feels no motion.
The principle expressed by Newton’s first law is that there is no way to say which inertial observer is “really” moving and which is “really” standing still.
One observer’s state of rest is another observer’s state of uniform motion in a straight line, and no experiment can deem either point of view to be correct or incorrect.
There is no absolute standard of rest
Newton himself believed that absolute space and time existed, but that the only measures of space or time accessible to experiment are relative
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*👨🔬🕵️♀️🙇♀️*SKETCHES*🙇♂️👩🔬🕵️♂️*
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👈👈👈☜*-NEWTON’S 3 LAWS OF MOTION-* ☞ 👉👉👉
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💕💝💖💓🖤💙🖤💙🖤💙🖤❤️💚💛🧡❣️💞💔💘❣️🧡💛💚❤️🖤💜🖤💙🖤💙🖤💗💖💝💘
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*🌈✨ *TABLE OF CONTENTS* ✨🌷*
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🔥🔥🔥🔥🔥🔥*we won the war* 🔥🔥🔥🔥🔥🔥