Ball inside Ball collision - stop bouncing

[TOdorus]

Not vector but physics really. You seem to understand vectors just fine, it's just that if an object doesn't generate any friction it will never stop. Well here we go:

// enterframe function 
function onFrame(e:Event):void 
{ 
    movement.y += 0.8; 
     
    ballDist.x = bigBall.x - smallBall.x; 
    ballDist.y = bigBall.y - smallBall.y; 
     
    // if the smaller ball is outside the bigger ball 
    // perform reaction 
    if(ballDist.len+smallBall.width/2 > bigBall.width / 2) 
    {     
        (....)
        //Friction is applied
        movement.x *= 0.5;
        movement.y *= 0.5; 
         
        /*if(movement.len < 0.4) //This is still quite a big number. I'd go with a value like < 0.000001
        { 
            movement.x = 0; 
            movement.y = 0; 
        }*/ 
    } else {
         //Friction is applied
         movement.x *= 0.95;
         movement.y *= 0.95; 
    }
    smallBall.x+=movement.x; 
    smallBall.y+=movement.y; 
} 

Unless the ball is in a vacuum, it generates friction by rubbing against the air or whatever gas it is in. This is considerably less friction then rubbing against a solid wall, but friction none the less.