Flash / Flex / ActionScript/Animation/Springs

Springs Animation

 
package {
    import flash.display.Sprite;
    import flash.events.Event;
    
    public class Main extends Sprite {
        private var _sprite:Sprite= new Sprite(  );
        private var _vx:Number = 20;
        private var _vy:Number = 0;
        private var _k:Number = .1;
        private var _damp:Number = .94;
        private var _targetX:Number = 200;
        private var _targetY:Number = 200;
        
        public function Main(  ) {
            _sprite.graphics.beginFill(0x0000ff, 100);
            _sprite.graphics.drawCircle(0, 0, 5);
            _sprite.x = 0;
            _sprite.y = 0;
            addChild(_sprite);
            addEventListener(Event.ENTER_FRAME, onEnterFrame);
        }
        
        public function onEnterFrame(event:Event):void {
            var ax:Number = (_targetX - _sprite.x) * _k;
            var ay:Number = (_targetY - _sprite.y) * _k;
            _vx += ax;
            _vy += ay;
            _sprite.x += _vx;
            _sprite.y += _vy;
            _vx *= _damp;
            _vy *= _damp;
        }
    }    
}

Using Trigonometry

 
package {
    import flash.display.Sprite;
    import flash.events.Event;
    
    public class Main extends Sprite {
        private var _sprite:Sprite;
        private var _angle:Number = 45;
        private var _radius:Number = 200;
        
        public function Main(  ) {
            _sprite = new Sprite(  );
            _sprite.graphics.beginFill(0x0000ff, 100);
            _sprite.graphics.drawCircle(0, 0, 5);
            _sprite.graphics.endFill(  );
            _sprite.x = 0;
            _sprite.y = 100;
            addChild(_sprite);
            addEventListener(Event.ENTER_FRAME, onEnterFrame);
        }
        
        public function onEnterFrame(event:Event):void {
            _sprite.x = 200 + Math.sin(_angle) * _radius;
            _angle += .05;
        }
    }    
}