How to remove web application using PowerShell 2010

Method 1:

Remove-SPWebApplication -Identity http://ukreddy:6789

This cmdlet will ask for user's confirmation.

Remove-SPWebApplication -Identity http://ukreddy:6789 -Confirm:$false

This cmdlet won't ask for user's confirmation.

This cmdlet permanently removes the Web application at http://ukreddy:6789. This command does not remove the content databases or the IIS Web site.

Method 2:

Remove-SPWebApplication -Identity http://ukreddy:6789 -DeleteIISSite -RemoveContentDatabase

This cmdlet will ask for user's confirmation.

Remove-SPWebApplication -Identity http://ukreddy:6789  -Confirm:$false -DeleteIISSite -RemoveContentDatabase

This cmdlet won't ask for user's confirmation.

This cmdlet permanently removes the Web application at http://ukreddy:6789. This command also remove the content databases or the IIS Web site.