document ready function accordion h3 first addClass active accordion n

$(document).ready(function(){
    $(".accordion h3:first").addClass("active");
    $(".accordion p:not(:first)").hide();
    $(".accordion h3").click(function(){
        $(this).next("p").slideToggle("slow")
        .siblings("p:visible").slideUp("slow");
        $(this).toggleClass("active");
        $(this).siblings("h3").removeClass("active");
     });
 });