How would I reduce jittering on this RigidBody2D?

So I have this code where it does what I want by moving the player behind the mouse and having a variable speed depending on how far away it is from the cursor, but it jitters a lot. I don't understand how I would fix this annoying problem and smooth it out, since I'm new to C#. Could it be because of the AddForce? There might be another was to do this that I don't know about. I would be very greatful if you could help me understand this, thanks!

     void FixedUpdate () {
         //Follow the mouse
             var pos = Input.mousePosition;
             pos = Camera.main.ScreenToWorldPoint(pos);
             var dir = pos - transform.position;
             rigidbody2D.AddForce(dir * 4);
     }