Version: 2018.2
public Vector2 relativeVelocity ;

Description

Относительная линейная скорость двух столкнувшихся объектов (Read Only).

// Play a sound when we hit an object with a big velocity
using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour { AudioSource audioSource;

void Start() { audioSource = GetComponent<AudioSource>(); }

void OnCollisionEnter2D(Collision2D collision) { if (collision.relativeVelocity.magnitude > 2) audioSource.Play(); } }