---
title: "Reference Frame — AP Physics C: Mechanics Definition"
description: "A reference frame is the coordinate system and observer viewpoint you measure motion from. It anchors kinematics in Unit 1 and decides where Newton's laws apply."
canonical: "https://fiveable.me/ap-physics-c-mechanics/key-terms/reference-frame"
type: "key-term"
subject: "AP Physics C: Mechanics"
---

# Reference Frame — AP Physics C: Mechanics Definition

## Definition

A reference frame is a coordinate system used to describe the motion of an object. It provides a point of reference for measuring positions, velocities, and accelerations.

## Related Study Guides

- [1.1 Kinematics Overview and Motion in One Dimension](/ap-physics-c-mechanics/unit-1/kinematics-motion-one-dimension/study-guide/pjrFyrB3flgyHYTnfCCO)

## Review

### Related Terms

- Inertial Frame: An inertial frame is a special type of reference frame where Newton's laws of motion hold true without any external forces acting on it.
- Non-inertial Frame: A non-inertial frame is a reference frame that is accelerating or rotating. In this type of frame, additional fictitious forces need to be considered.
- Relative Motion: Relative motion refers to the movement of an object with respect to another object or observer. It describes how one object's motion appears from the perspective of another object or observer.