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# ForceMode.impulse

A direct adjustment to a body’s linear or angular momentum.

```
case impulse
```

## Discussion

The quantity that user sets via [`setForce(_:index:)`](/documentation/RealityKit/ForceEffectParameters/setForce(_:index:))
has the units of mass * distance / time.
`impulse` mode causes a change in linear momentum.

The quantity that user sets via [`setTorque(_:index:)`](/documentation/RealityKit/ForceEffectParameters/setTorque(_:index:))
has the units of mass * distance^2 / time.
`impulse` mode causes a change in angular momentum.

---

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