---
title: yAcceleration
framework: spritekit
role: symbol
role_heading: Instance Property
path: spritekit/skemitternode/yacceleration
---

# yAcceleration

The acceleration to apply to a particle’s vertical velocity.

## Declaration

```swift
var yAcceleration: CGFloat { get set }
```

## Discussion

Discussion This property is useful for simulating wind, gravity and other effects. It is uniformly applied to all particles generated by the emitter. The default value is 0.0.

## See Also

### Controlling Particle Velocity and Acceleration

- [particleSpeed](spritekit/skemitternode/particlespeed.md)
- [particleSpeedRange](spritekit/skemitternode/particlespeedrange.md)
- [emissionAngle](spritekit/skemitternode/emissionangle.md)
- [emissionAngleRange](spritekit/skemitternode/emissionanglerange.md)
- [xAcceleration](spritekit/skemitternode/xacceleration.md)
- [particleZPositionSpeed](spritekit/skemitternode/particlezpositionspeed.md)