Answers for "how to check first radio button checked or not using jquery"

check radio button is checked jquery

$(document).ready(function(){
  $('#submit_button').click(function() {
    if (!$("input[name='name']:checked").val()) {
       alert('Nothing is checked!');
        return false;
    }
    else {
      alert('One of the radio buttons is checked!');
    }
  });
});

get checked radio button value jquery by name

$('input[name="name_of_your_radiobutton"]:checked').val();