100 seconds

How it works

How it works is a hundred SI seconds, then a spelling. Sixty seconds make one minute, so 100 ÷ 60 = 1 remainder 40. Keep the remainder as seconds. Write 1 min 40 s, 1:40 when the last field is seconds, 00:01:40 as hh:mm:ss elapsed, 100 s, or PT1M40S. Rounding 1:40 to “about two minutes” adds 20 seconds you do not have. Rounding it to one minute drops 40 seconds you do have. The remainder is the point of this count.

Decimal minutes for 100 seconds are 100/60 = 5/3 minutes, which is 1.6̅ minutes, not 1.40 and not 1.00. 1.40 minutes would be 1 minute plus 0.40 × 60 seconds, which is 24 seconds, total 84 seconds. 1.00 minutes is 60 seconds. Decimal hours are 100/3,600 hours, a small fraction, not 0.100 hours: 0.100 hours is 6 minutes, which is 360 seconds. Copying 100 after a point does not convert it.

A hundred on a scoreboard is a count of points, laps, or something else until the header says seconds. A clock face that shows 1:00 is one o’clock or one minute, depending on fields, and is not 100 seconds either way. 1:40 as a time of day is twenty to two. 1:40 as m:ss elapsed is this page. Field names first, digits second.

100 s = 1 min 40 s 100 s = 5/3 min 90 s = 1 min 30 s 120 s = 2 min 100 ms = 0.1 s, not 100 s

1:40 versus 1.00 and 100

1:40 is this span only as minutes:seconds of elapsed time. 1.40 as a decimal hour is 1 hour 24 minutes. 1.40 as a decimal minute is 84 seconds, as above. 100 as a bare integer is a hundred of whatever the column is. 100:00 as mm:ss would be 100 minutes, which is 6,000 seconds. 1:00:00 as hh:mm:ss is one hour, 3,600 seconds. None of those are 100 seconds except 1:40 as m:ss and 00:01:40 as hh:mm:ss and 100 s.

ISO form PT100S and PT1M40S are the same length. PT1M40S is easier to read. PT100S is harder to confuse with one hundred minutes (PT100M). PT1.6667M is a rounded decimal minute; 5/3 is exact. Prefer the integer-second form or the minute-plus-remainder form when a parser is picky.

A hundred seconds is a minute and forty that keeps pretending to be a round score. The score is the unit. The unit is seconds.

Milliseconds, and a hundred of something else

100 milliseconds is 0.1 seconds, one thousand times shorter than 100 seconds. 100 microseconds is shorter again. If a profiler prints 100 and the column is ms, you have a tenth of a second. If the column is s, you have 1:40. If the column is minutes, you have 100 minutes. The conversion for this heading is only the seconds column: divide by 60, keep 40.

100 seconds is not 100 o’clock, and it is not a century. It is not 1% of anything unless you named the whole. A timeout of 100 seconds is 1:40 of waiting. A clip of 100 seconds is 1:40 of runtime. A speech of 100 seconds is 1:40 of talking. Each of those can wear 00:01:40. Only the unit “seconds” makes the hundred honest.