How would I hide the webform in drupal7 after user's(authenticated user) first submission.Later the user should not be able to view the webform again. Please help me on this.
After creating your webform, go to the "Form Settings" under "Webform". In case you don't find it, here's the URL: node/Nid/webform/configure (I choose not to remind you of the Nid that you should change :)).
Here, you should see an option for "Per User Submission Limit"- In your scenario, Limit each user to "1" submission(s) "ever".