Jquery function not identified in Asp.net

Question

I have Client side function in Jquery name myFunction

function myFunction (){

alert('Hello');
}

on Server side I call this function using this code

ScriptManager.RegisterStartupScript(this.Page, this.GetType(), "tmp", "<script type='text/javascript'>$(function(){myFunction();});</script>", false);

it works fine when my Url is Home.aspx , and when I make a file of type Global.asax and make new Url from my home for example Home it also workes fine , but when I make another new Url for example Home/Category/1 this gives me a Javascript error saying that myFuntion is not defined

I searched and googled but couldnt get anything helpful.