I THINK that i have aplied a force of 1000 but it wont work

var simpleBulletPrefab : Transform;

function Update()
{
if(Input.GetButtonDown(“Jump”))
{
Instantiate(simpleBulletPrefab, transform.position, transform.rotation);

simpleBulletPrefab.rigidbody.AddForce(transform.forward * 1000);
}
}

var simpleBulletPrefab : GameObject;

function Update()
{
if (Input.GetButtonDown(“Jump”))
{
var aBullet : GameObject = Instantiate (simpleBulletPrefab, transform.position, transform.rotation) as GameObject;
aBullet.rigidbody.AddForce (transform.forward * 1000);
}
}
//ftfy