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# dampingFactor

A factor that slows particles relative to their velocity. Animatable.

```
var dampingFactor: CGFloat { get set }
```

## Discussion

Use this property to simulate effects such as fluid friction or air resistance on particles. A value of `0.0` (the default) specifies no slowing—that is, each particle maintains a constant speed (unless affected by gravity, acceleration, physics fields, or other influences). A value of `1.0` prevents particles from moving.

You can animate changes to this property’s value. See [Animating SceneKit Content](/documentation/SceneKit/animating-scenekit-content).

---

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