How to stop jitter with rigidbody2D

Hi, I have created a minimal 2D Program where I add Force to a Sprite with a rigidbody2D and a Collider2D. The Sprite is correctly animated according to 2D Physics but its not animating smoothly. It looks like the Sprite is jumping slightly back and forth. Deactivating VSync reduces the jittering but still not smooth. Setting the velocity directly results in the same outcome. The Force is applied on Mouse Down. The Script is placed on the Sprite. This can't be intentional right? Or am I already doing something wrong?

 public class BallBehaviour : MonoBehaviour {
 void OnMouseDown () {
         rigidbody2D.AddForce(new Vector2(150f,0f));
     }
 }