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# TimedForceFalloff

A type that modulates the force strength based on how long the force effect has run.

```
struct TimedForceFalloff
```

## Overview

Forces have the largest strength when the force effect starts to play and gradually decay to zero when approaching
the given duration. The effect also stops playing when reaching the duration.

Similar to [`SpatialForceFalloff`](/documentation/RealityKit/SpatialForceFalloff), [`rate`](/documentation/RealityKit/TimedForceFalloff/rate) controls how fast the force strength decays.
You can set the rate to zero to have a force effect with no temporal falloff.

```swift
let noTimedFalloff = TimedFalloff(duration: 1, rate: 0)
```

## Topics

### Initializers

[`init(duration: TimeInterval, rate: Double)`](/documentation/RealityKit/TimedForceFalloff/init(duration:rate:))

Creates a timed force falloff.

### Instance Properties

[`var duration: TimeInterval`](/documentation/RealityKit/TimedForceFalloff/duration)

The lifetime of the effect in seconds.

[`var rate: Double`](/documentation/RealityKit/TimedForceFalloff/rate)

The temporal falloff / attenuation rate.

---

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