RigidBody.velocity doesn't work for me

Hi. I am instantiating some objects with RigidBody attached. On spawn I would like to give objects some velocity, but it doesn’t work.
Also tried putting the code into FixedUpdate and tried using AddForce instead. Neither worked.

private void Drop()
    {
        foreach (GameObject drop in DropItems)
        {
            Instantiate(drop, transform.position, Quaternion.identity);
            Vector3 dropTrajectory = new Vector3(Random.Range(-1.0F, 1.0F), Random.Range(0, 1.0F), Random.Range(-1.0F, 1.0F));
            dropTrajectory = dropTrajectory.normalized;
            drop.GetComponent<Rigidbody>().velocity = dropTrajectory * 100;
        }
    }

Hope You can point out which important aspect of Unity I missed.

private void Drop()
{
foreach (GameObject drop in DropItems)
{
GameObject newdrop = Instantiate(drop, transform.position, Quaternion.identity);
Vector3 dropTrajectory = new Vector3(Random.Range(-1.0F, 1.0F), Random.Range(0, 1.0F), Random.Range(-1.0F, 1.0F));
dropTrajectory = dropTrajectory.normalized;
newdrop.GetComponent().velocity = dropTrajectory * 100;
}
}

Try this.