Ajax google image search - random thumbnail

gimage-search.js

$.ajax({
  dataType: "jsonp",
  url: 'http://ajax.googleapis.com/ajax/services/search/images',
  data: {
    v: "1.0",
    rsz: 8,
    q: "airplane"
  },
  success: function ( json ) {
    var rand = Math.floor(Math.random() * json.responseData.results.length),
        results = json.responseData.results;
    
    $('img').attr('src', results[rand].tbUrl);
  }
});