Trying to give my instantiated object an initial velocity. (Arkanoid type game)

I have an object which is created as a result of the player picking up a powerup. The powerups purpose to to duplicate the object and this is working properly, but I want to add to this and give the created object an initial velocity. I think I have come pretty close from looking through older unity forums from around 2011, but the language has changed a bit from then so I'm struggling to connect the final piece of this formula. What I have so far is this:

 public class Multiball : MonoBehaviour
 {
    [SerializeField] Ball ball;
     public void OnTriggerEnter2D(Collider2D PowerUp)
     {
         if (PowerUp.gameObject.name == "Paddle")
         {
             Multiply();
             Destroy(gameObject);
         }
     }
     public void Multiply()
     {
         Ball powerup = Instantiate(ball, transform.position, transform.rotation) as Ball;
         ball.GetComponent<Rigidbody2D>().velocity = /* SET A VELOCITY HERE? */
     }
 
 }

How would I give this object a velocity of my ball object ideally. Once the player picks up the powerup with their paddle, I'd like the powerups instantiation to give the instantiated ball a velocity equal to that of the original ball.