ActionScript 3.0 :: Creating A Preloader And Progress Bar?

the image I load using the tutorial loads really fast (it's only 240kb) which basically means that the progress bar just blinks and completes so fast that people who don't know what's going on won't know what just blinked.

My question therefore is this:Is it possible to tell the preloader, that even if the image is already loaded, the progress bar will take for example 2 seconds to complete?

That way people with fast connections will see the preloader for 2 seconds and people with slower connections will see the preloader for whatever time it takes to load the image.

Here's the code from the tutorial:

Code:
var imageLoader:Loader;
function loadImage(url:String):void {
// Show Preloader
preloader_projekt1.visible = true;

[code]....