How many grooves are there on one side of an average LP record?
It's an old, silly saying or joke. How many grooves on a record? The answer, of course, is two. There is just one standard groove on each side of a record—and the groove is usually about 1,500 feet long, or about 1/3 of a mile. Each side which has the groove will spiral inwardly in such a narrow pattern that it looks almost like concentric circles.
In addition, some records which are made as test pressings and not standard for albums and singles (either vinyl, acetate or some other less durable material) have often been created as a double-disc set, with one side of each disc being blank. Doing this makes it quicker and easier to press a single side of a record twice. It takes far more time and effort to press two different sides of a single record. Furthermore, artists on a stritch budget, at a time when vinyl was prevalent, could more often pay for a single-sided pressing, and some DJs past and present want single-sided records for reasons typically outlined in having a one-sided LP.