Am i doing wrong to define, jQuery Accordion inside my .module file, just like this:
<?php drupal_add_library('system', 'ui.accordion');
Drupal no longer loading jquery itself.
You can add below code in your theme template.php
Yes that's wrong, you need to put it inside a hook function.
Which one depends on where you're trying to use it. To add it to a render array, for example a form, you might use