title: OnCollisionEnter() not working in Unity3D
body: <p>I have an object with a mesh collider and a prefab with sphere collider. I want the instance of the prefab to be destroyed if the two collide.</p>
  
  <p>I wrote the following in a script:</p>
  
  <pre><code>private void OnCollisionEnter(Collision c)
  {
      if (c == target)
          Destroy(transform.gameObject);
      print("something");                   // Doesn't get printed
  }
  </code></pre>
  
  <p>But it is not working. I have tried toggling <code>isTrigger</code> on both the objects.</p>