title: Unity falling platform passes through ground while falling
body: <p>I got a Cube with a box collider and a trigger on it. When the player stands on it, it falls down. </p>
  
  <p>I want the platform to destroy itself after colliding with something and before that, instantiate itself at its starting position.</p>
  
  <p>So my code looks this:</p>
  
  <pre><code>void OnTriggerEnter(Collider col)
  {
      if (col.CompareTag("Player"))
          isFalling = true;
  }
  
  void OnCollisionEnter(Collision col)
  {
      if (!col.gameObject.CompareTag("Player"))
      {
          Instantiate(gameObject, startPosition, startRotation);
          Destroy(gameObject);
      }
  }
  
  void Update()
  {
      if (isFalling)
      {
          fallingSpeed += Time.deltaTime / 20;
          transform.position = new Vector3(transform.position.x, transform.position.y - fallingSpeed, transform.position.z);
      }
  }
  </code></pre>
  
  <p>Well when my platform crashes down, it just passes through the ground. There is even no collision detected.</p>
  
  <p>Does someone got a hint for me?</p>