Add force in the direction that raycast gets hit

Hi, im trying to make a fighting game, and i have two questuion.
So for the punch I'm using raycasting to determine if its hit something and here is the code:

Code (CSharp):

1.     void Shoot ()
2.     {
3.            
4.         shootRay.origin = rightHand.transform.position;
5.         shootRay.direction = transform.forward;
6.        
7.         if(Physics.Raycast (shootRay, out shootHit, range, shootableMask))
8.         {
9.             Debug.DrawLine(rightHand.transform.position, shootHit.transform.position, Color.red,2.0f);
10.  
11.             Rigidbody enemyrigid = shootHit.collider.GetComponent <Rigidbody> ();
12.  
13.  
14.             // If the EnemyHealth component exist...
15.             if(enemyrigid != null)
16.             {
17.  
18.  
19.                 //enemyrigid.AddForce(shootRay.origin + shootRay.direction * punchPower ,ForceMode.VelocityChange);  // Not sure if i should use AddForce Or Velocity
20.                 enemyrigid.velocity = (shootHit.point - rightHand.transform.position).normalized * punchPower;
21.  
22.                
23.             }
24.            
25.         }
26.  
27.         else
28.         {
29.             Debug.Log(“Didn’t Hit Anything”);
30.            
31.         }
32.     }

So my question is:
1. My main question is when i hit Fire Button it shoots ray from like right hand to Shootable thing so im gonna add force in the direction that Raycast draw, is there anyway so i can do it ? you can see the image example

http://i.imgur.com/0O3MNrV.jpg?1

2. Should i use AddForce or Velocity to move the enemie backward? is there any diffrence? because i tried both of them and both works the same!

 

What do you use for raycasting? Every raycast has a direction variable. You can just use AddForce with that direction in it. You could also set the forcemode to velocitychange, so its "instant".