Clock Hands Overlap Time

Also known as when do clock hands overlap · clock hands coincide · hands of a clock together · clock overlap formula

M=60H11M = \frac{60H}{11}

Units aren’t used in this calculation — every value is a plain number.

Worked example: 1 o'clock → hands overlap 60/11 = 5.4545 min pastpress Try an example to run it live, then adjust anything.

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Learning zone

The hands overlap when the minute hand has lapped its way back onto the hour hand — and because it gains 5.5° per minute on a 30H-degree head start, that happens 60H/11 minutes past H. The eleven is the nugget: in 12 hours the minute hand laps the hour hand exactly 11 times, not 12, because the hour hand keeps walking away during the chase. That is why the overlaps land at odd, un-round times — 1:05:27, 2:10:54 — every one of them a multiple of the same 65 minutes and 5 5/11 seconds.

Watchmakers' trivia with teeth: the 11 overlaps per half-day is a fixed fact of any two-handed clock, fast or slow — a clock that gains time still overlaps 11 times per 12 of ITS OWN hours. The count is geometry, not timekeeping.

Clock Hands Overlap Time
M=60H11M = \frac{60H}{11}
Where
  • MM= Minutes past H o'clock
  • HH= Hour just struck
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