The specifics of how data is physically arranged across multiple platters is undocumented, complicated, and varies between models. But with some clever benchmarks, much of that information can be inferred: https://blog.stuffedcow.net/2019/09/hard-disk-geometry-micro...

A hard drive will only use one head on one platter at a time. A single logical block will be contained within a single track on one platter. The next logical block will usually be on the same track or an adjacent track on the same platter. Seeking from one track to the next using the same head is generally a bit quicker than switching to a different head on a different platter and getting it lined up with a nearby track.