I notice you have not set the key in this line:
var send = 'https://www.googleapis.com/language/translate/v2?key=My Key&source=en&target=iw&callback=translateText&q=translate+is+fast' + sourceText;
The Google translate API is no longer free: https://developers.google.com/translate/v2/pricing
] so you'll need to register (to get a key I assume).
As for the rest of the code, I don't know whether it will work or not. You will have more luck on Google developer groups as they'll have one dedicated to the translate api.