How to add a downward force to an Instantiated prefab?
<p>I am trying to get my prefabs to just fall at some speed.  Right now they get created and then gravity acts on it, so it starts off slow and then builds as it is in the air.  I want it to be a constant speed from the moment it is created.</p>

<p>I have tried doing an AddForce, but that doesn't seem to work.</p>

<pre><code>void Wave1()
{
    Debug.Log("Wave1");
    delay = .5f;
    Instantiate(smallFlame, new Vector3(drop1, dropHeight, 0), Quaternion.identity);
    Instantiate(smallFlame, new Vector3(drop2, dropHeight, 0), Quaternion.identity);
    Instantiate(smallFlame, new Vector3(drop3, dropHeight, 0), Quaternion.identity);

    smallFlame.GetComponent&lt;Rigidbody2D&gt;().AddForce(new Vector2(0, fallSpeed), ForceMode2D.Impulse);
}
</code></pre>