Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
An inertial reference frame is a coordinate system in which Newton's laws of motion hold true and there are no external forces acting on an object. It is a frame of reference that is not accelerating or rotating.
Related terms
Accelerating Reference Frame: A reference frame in which an object experiences acceleration due to external forces.
Non-inertial Reference Frame: A reference frame that is either accelerating or rotating, where Newton's laws of motion do not hold true.
Galilean Principle of Relativity: The principle stating that the laws of physics are the same in all inertial reference frames.