Simple error.....

I don’t know whats wrong error I get is

The best overloaded method match for `UnityEngine.Rigidbody.AddForceAtPosition(UnityEngine.Vector3, UnityEngine.Vector3, UnityEngine.ForceMode)’ has some invalid arguments

and

Argument #1' cannot convert UnityEngine.Transform’ expression to type `UnityEngine.Vector3’

    void Start ()
using UnityEngine;
using System.Collections;

public class RocketPropulsion : MonoBehaviour {
    public float speed;
    public float muzzleVelocity;
    public float burnTime;
    public float averageThrust;
    public float spinRate;
    public float velocityAtLauncherExit;
    public float accelerationInitial;
    public float accelerationFinal;
    public Transform endOfRocket;
    public Transform frontOfRocket;

    //Technical data for the rocketMotor





    // Use this for initialization
    void Start () 
    {
        GetComponent<Rigidbody> ();
        Rocket ();
    }
   
    // Update is called once per frame
    void Rocket () 
    {
        endOfRocket.transform.position = new Vector3(); //This is where the force is coming from.

        frontOfRocket.transform.position = new Vector3();

        rigidbody.AddForceAtPosition (frontOfRocket, endOfRocket, ForceMode.VelocityChange); // frontofrocket is the vector3 force or where the force is going.
       
    }
}

These are transforms. A transform according to the docs can contain many other things like a rotation and a position. You probably meant: rigidbody.AddForceAtPosition(frontOfRocket.position, endOfRocket.position

This still won’t yield superb results though because: Unity - Scripting API: Rigidbody.AddForceAtPosition states that the first parameter is the FORCE you want to use, so this would probably be a Vector3 of the force you’d like to propel it by. The second parameter is the position you’d like to apply the force.

Thanks mate