How to add js file in only 1 node?
In the template.php you will write this small piece of code:

function MYTHEME_preprocess_node($vars) {
 if (drupal_get_path_alias("node/{$vars['#node']-&gt;nid}") == 'yournid') {
    drupal_add_js(drupal_get_path('theme', 'MYTHEME') . "/script/js");
 }
}


Replace foo with values related to your need.