---
title: restitution
framework: scenekit
role: symbol
role_heading: Instance Property
path: scenekit/scnphysicsbody/restitution
---

# restitution

A factor that determines how much kinetic energy the body loses or gains in collisions.

## Declaration

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

## Discussion

Discussion This property simulates the “bounciness” of a body. A restitution of 1.0 means that the body loses no energy in a collision—for example, a ball dropped onto a flat surface will bounce back to the height it fell from. A restitution of 0.0 means the body does not bounce after a collision. A restitution of greater than 1.0 causes the body to gain energy in collisions. The default restitution is 0.5.

## See Also

### Defining a Body’s Physical Properties

- [mass](scenekit/scnphysicsbody/mass.md)
- [charge](scenekit/scnphysicsbody/charge.md)
- [friction](scenekit/scnphysicsbody/friction.md)
- [rollingFriction](scenekit/scnphysicsbody/rollingfriction.md)
- [damping](scenekit/scnphysicsbody/damping.md)
- [angularDamping](scenekit/scnphysicsbody/angulardamping.md)
- [momentOfInertia](scenekit/scnphysicsbody/momentofinertia.md)
- [usesDefaultMomentOfInertia](scenekit/scnphysicsbody/usesdefaultmomentofinertia.md)
- [centerOfMassOffset](scenekit/scnphysicsbody/centerofmassoffset.md)