What goes at the rate of 15 seconds per second?
15x fast forward on my DVD player
The hour hand on a 24 hour clock
dontdisturbmycircles might be right, I never timed it. But daveb is certainly right. The answer I was looking for was the earth spinning on its axis. 15 seconds of arc per 1 second of time.
There's a perfectly good reason why no one times clocks. It's based on assumption but it's pretty reliable even if you didn't have acces to any technology, you'd quickly be able to see whether your clock was accurate, just by going outside once in a blue moon, or if you worked by seeing the expression on your bosses face, either delight at you being so prompt or scorn at you being so late.
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