phone no must be 10 digits in jquery code example

Example: jquery only number allowed to 10 digit

<script type="text/javascript">
  $(document).ready(function() {	
  $("#phone_work").attr("maxlength", "10");
  $("#phone_work").keypress(function(e) {
    var kk = e.which;
    if(kk < 48 || kk > 57)
      e.preventDefault();
  });
});
</script>