jQuery Forum

There are two parameters that are passed to the drag callback/event:
the event object and a ui hash containing details about the event. In
the case of drop, the element that was dropped is stored in
ui.draggable.
$(el).droppable({
drop: function(event, ui) {
console.log(ui.draggable);
}
});
See http://jqueryui.com/docs/droppable/#event-drop for the
documentation (click the "show details" link at the top of the
section).