Adding Rigidbody to an Object on Collision by Raycast?

I have a plank shelter type of building and I want it's planks to fall off(add a rigidbody) when I shoot it with the raycast(bullets). This is an FPS game by the way.

My current script can add force to a rigidbody. BUT, I need HELP making the planks on the plank building to add a rigidbody to it when it's hit by a raycast.

This is my current code, Please please refine/fix it and post back please =)

 function RayShoot (){
 
 
             
    
                                                                                    
         var hit : RaycastHit;
 
                 
                  var direction : Vector3  = transform.TransformDirection(Vector3.forward);
          
                 Debug.DrawRay(transform.position , direction * Range , Color.blue);
                 
                 if(Physics.Raycast(transform.position , direction , hit, Range)){
         
                 if(hit.rigidbody){
                       
                 hit.rigidbody.AddForceAtPosition( direction * Force , hit.point);
                 
                 }
                 if (hit.gameObject){
                 GameObject Plank = GameObject.FindGameObjectsWithTag("plank");
                 Plank.AddComponent.rigidbody;
                 }
                 
                 }
         
                 
                 
                 
                 
                 BulletsLeft --;
                  
             
                 if(BulletsLeft < 0){
                 
                 BulletsLeft = 0;
                 
                 }
                 
                 if( BulletsLeft == 0 ){
                 
                 if(Input.GetKey(KeyCode.R)){
                 
                 
                 Reload();
                 
                 }
                 
                 
                 }
 
                 }