Please help with raycasting on touch to add force to a gameobject (Android)

Hi, I am trying to write code that will add force to a gameobject when the player touches them on the screen.

I have tried with the following code but it just doesn't work at all when I build and run on my phone. I cant for the life of me see the error in my code here, so perhaps someone could point out where I have gone wrong?

Basically, nothing happens when you touch the object, it just falls.

Here is the code I am using:

     public float forceUpMin;
     public float forceUpMax;
     public float forceSideMin;
     public float forceSideMax;
 
     public float spinMin;
     public float spinMax;
 
     Vector3 force;
     float forceX;
     float forceY;
     float forceZ = 0.0f;
     Vector3 randomTorque;
     
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update()
     {
 
         for (var i = 0; i < Input.touchCount; ++i)
         {
             if (Input.GetTouch(i).phase == TouchPhase.Began)
             {
                 RaycastHit hit;
                 Ray ray = Camera.main.ScreenPointToRay(Input.GetTouch(i).position);
                 if (Physics.Raycast(ray, out hit))
                 {
                     if(hit.collider.tag == "Can")
                     {
                         ShootCan(hit.collider.gameObject);
                     }
                 }
             }
 
         }
 
         if(lives == 0)
         {
             GameOver();
         }
     }
 
     public void ShootCan(GameObject go)
     {
         forceX = Random.Range(forceSideMin, forceSideMax);
         forceY = Random.Range(forceUpMin, forceUpMax);
 
         force.x = forceX;
         force.y = forceY;
         force.z = forceZ;
 
         randomTorque.x = Random.Range(-spinMin, spinMax);
         randomTorque.y = Random.Range(-spinMin, spinMax);
         randomTorque.z = Random.Range(-spinMin, spinMax);
 
         go.GetComponent<ConstantForce>().torque = randomTorque;
         go.GetComponent<Rigidbody>().AddForce(force);
     }