Ball.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Ball : MonoBehaviour {

	public float lifeTime = 10f;
    public bool inWindZone = false;
    public GameObject windZone;

    Rigidbody rb;

    private void Start()
    {
        rb = GetComponent<Rigidbody>();
    }

    // Update is called once per frame
    void Update()
	{
		if (lifeTime > 0)
		{
			lifeTime -= Time.deltaTime;
			if (lifeTime <= 0)
			{
				Destruction();
			}
		}

		if (transform.position.y <= -20)
		{
			Destruction();
		}
	}

    //private void FixedUpdate()
    //{
    //    if(inWindZone) {
    //        rb.AddForce(windZone.GetComponent<WindArea>().direction * windZone.GetComponent<WindArea>().strength);
    //    }
    //}

    //void OnTriggerEnter(Collider coll) {
    //    if(coll.gameObject.tag == "windArea") {
    //        windZone = coll.gameObject;
    //        inWindZone = true;
    //    }
    //}

    //void OnTriggerExit(Collider coll) {
    //    if(coll.gameObject.tag == "windArea") {
    //        inWindZone = false;
    //    }
    //}

	void OnCollisionEnter(Collision coll)
	{
		if (coll.gameObject.name == "destroyer")
		{
			Destruction();
		}
	}

	void Destruction()
	{
		Destroy(this.gameObject);
	}
}