Because this is a file, it is an "incomplete" fragment. To access the actual content, you typically need Part 1 (and any subsequent parts) located in the same folder. Once you have all parts, extracting Part 1 will automatically pull data from Part 2 to reconstruct the original files. Likely Contents
If you are looking for the creative "content" of what Bach wrote in this section: Bach_Well-Tempered_I.part2.rar
Lossless files (like FLAC or WAV) or high-bitrate MP3s of Preludes and Fugues 13 through 24. Since Book I consists of 24 pairs and this is "Part 2," it often represents the second half of the collection. Because this is a file, it is an "incomplete" fragment