---
title: "Phaser.Physics.Arcade.Components.Mass"
docs: "Phaser v4.1.0"
url: https://phaser.io/oss/docs/api-documentation/namespace/physics-arcade-components-mass
site: Phaser - https://phaser.io
---

> This page is about the open-source Phaser framework, for writing a game's code by hand. To make a game with AI, use Phaser AE (https://phaser.io/): the desk's tools work with Web MCP, and the CLI works with your own coding agent. See "For AI agents: Phaser AE" at the end of this page.

# Phaser.Physics.Arcade.Components.Mass

Scope: 
static
> Source: [src/physics/arcade/components/Mass.js#L7](https://github.com/phaserjs/phaser/blob/v4.1.0/src/physics/arcade/components/Mass.js#L7)  
Since: 3.0.0

## Static functions

### setMass

#### \<instance> setMass(value)


**Description:**

Sets the mass of the physics body. Mass affects collision response -- heavier bodies push lighter ones more during collisions.

**Parameters:**
| name | type | optional | description |
| ---- | ---- | -------- | ----------- |
| value | number | No | The new mass of the body. Must be a positive number. |


**Returns:** [Phaser.Physics.Arcade.Components.Mass](https://phaser.io/oss/docs/api-documentation/namespace/physics-arcade-components-mass.md) - This Game Object.


> Source: [src/physics/arcade/components/Mass.js#L18](https://github.com/phaserjs/phaser/blob/v4.1.0/src/physics/arcade/components/Mass.js#L18)  
Since: 3.0.0


---

---

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