unity3d 增加子弹碰撞后物体的爆炸力

using UnityEngine;

public class Bullet : MonoBehaviour {

    public GameObject bulletEffecte;
    // Use this for initialization
    void Start () {

    }

    // Update is called once per frame
    void Update () {
        Destroy(gameObject,3f);
    }
    void OnCollisionEnter(Collision e)
    {
        Instantiate(bulletEffecte,transform.position,transform.rotation);
        Destroy(gameObject);

        if(e.gameObject.tag =="Cube")  //如果目标的标签是cube
        {
            //将球形的(OverlapSphere)的物理引擎(Physics) 放在一个碰撞体的数组里
            Collider[] collider = Physics.OverlapSphere(transform.position,2);  
           //便利这个数组
            foreach (Collider c in collider)
            {
                Rigidbody r = c.GetComponent<Rigidbody>(); //获得这个数组里的元素的刚体
                if(r != null)    //如果刚体不是空的
                {
                    r.AddExplosionForce(1000, transform.position, 3);//增加爆炸力(AddExplosionForce) (爆炸的力,爆炸点,爆炸范围)
                }
            }

        }
    }
}