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# ForceMode.acceleration

A direct adjustment to a body’s linear or angular acceleration, independent of its mass or inertia.

```
case acceleration
```

## Discussion

The quantity that user sets via [`setForce(_:index:)`](/documentation/RealityKit/ForceEffectParameters/setForce(_:index:))
has the units of distance / time^2.
`acceleration` mode causes a change in acceleration independent of a body’s mass.

The quantity that user sets via [`setTorque(_:index:)`](/documentation/RealityKit/ForceEffectParameters/setTorque(_:index:))
has the units of 1 / time^2 or radian / time^2.
`acceleration` mode causes a change in angular acceleration independent of a body’s mass or inertia.

---

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