EasyRay.cs

var ray = cam.ScreenPointToRay(TouchScreenWrap.touches[0].position);
            RaycastHit hit;
            if (Physics.Raycast(ray, out hit)) { 
                if (hit.transform.GetComponent<Rigidbody>() != null)
                {
                    Vector3 offSet = hit.transform.position - cam.transform.position;
                    hit.transform.GetComponent<Rigidbody>().AddForce(offSet.normalized * Force, ForceMode.VelocityChange);

                }
            }