---
title: "Center of Mass — AP Physics C Mechanics Definition & Guide"
description: "Center of mass is the mass-weighted average position of a system, where x_cm = Σmx/M. It links Newton's laws, momentum conservation, and rotation on AP Physics C."
canonical: "https://fiveable.me/ap-physics-c-mechanics/key-terms/center-of-mass"
type: "key-term"
subject: "AP Physics C: Mechanics"
---

# Center of Mass — AP Physics C Mechanics Definition & Guide

## Definition

The center of mass is the point in an object or system where its mass can be considered to be concentrated. It is the average position of all the particles that make up the object.

## Related Study Guides

- [AP Physics C: Mechanics Exam Guide](/ap-physics-c-mechanics/unit-XFAHq6btBZc5gQPX/2024-ap-physics-c-mechanics-exam-guide/study-guide/noMpjoQ3vOhzWeMth8ML)
- [4.1 Center of Mass ](/ap-physics-c-mechanics/unit-4/center-mass/study-guide/pleJdgx4XYiy12T34nmN)
- [Unit 5 Overview: Rotation ](/ap-physics-c-mechanics/unit-kzIqRYNyrRNrQ2fb/review/study-guide/uZDIVVGRg4RtNODqFuAd)

## Review

### Related Terms

- [Mass](/ap-physics-c-mechanics/key-terms/mass): The amount of matter in an object.
- Weight: The force exerted on an object due to gravity.
- [Torque](/ap-physics-c-mechanics/key-terms/torque): A measure of how effectively a force causes rotation.