When two frames of reference are moving relative to each other at constant velocity, they are said to be inertial reference frames. The observers from two such inertial frames measure, in general, different velocities of a moving particle. On the other hand, they measure the same acceleration for the particle. The laws of physics must have the same form in all inertial reference frames (the principle of invariance).
Generalic, Eni. "Inertial reference frames." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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