If you turn off the PC, remove the drive, and try to read it, it should be gobbledy-gook.
(Similarly, if you make an image of the drive and then try to read the image, it will be gobbledy-gook.)
If your PC is running, and you copy the file to other media (thumb drive, USB hard drive, floppy disk, network storage, etc), the file will be unencrypted on the new media (unless the media has its own encryption scheme).
We tell our customers that encrypting backup media is more dangerous than simply backing up and storing the backup media securely. In a disaster recovery situation, you're generally happy enough to have a good backup, let alone have a good backup and
be able to find the password and compatible encryption software.