Add Html Element with jQuery

<script type="text/javascript" src="jquery-1.7.1.min.js"></script>
<input type="radio" id="sample" name="sample" value="1" />
<input type="radio" id="sample" name="sample" value="2" />
<input type="radio" id="sample" name="sample" value="3" />

<script type="text/javascript">
<!--
    $(document).ready(function(){
    $("#sample").click(function(){
    if($('input[name=sample]:checked').val()=="1"){
        $('<input id="ok" type="text">').appendTo('#addText');
    }
    });
    });
    function test(){
        alert($("#ok").val());
    }
-->
</script>
<div id="addText"></div>

<input type="button" id="text" onclick="test();">