Guest Posted January 21, 2011 Report Share Posted January 21, 2011 How can you make a clock work at the normal rate (of one second per second) but only show the right hour exactly 2 times per day? Quote Link to comment Share on other sites More sharing options...
0 curr3nt Posted January 21, 2011 Report Share Posted January 21, 2011 Make it run backwards? How can you make a clock work at the normal rate (of one second per second) but only show the right hour exactly 2 times per day? Quote Link to comment Share on other sites More sharing options...
0 curr3nt Posted January 21, 2011 Report Share Posted January 21, 2011 backwards would make it correct at 6 and 12. Make the broken clock go back one second then repeat forward 2, back 2. broken correct 0:00:00 0:00:00 23:59:59 0:00:01 0:00:00 0:00:02 0:00:01 0:00:03 0:00:00 0:00:04 23:59:59 0:00:05 0:00:00 0:00:06 0:00:01 0:00:07 ... 23:59:59 11:59:57 0:00:00 11:59:58 0:00:01 11:59:59 0:00:00 12:00:00 23:59:59 12:00:01 0:00:00 12:00:02 0:00:01 12:00:03 with 0 being the same as 12. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 21, 2011 Report Share Posted January 21, 2011 (edited) My initial though, and probably what youre looking for, was that you would run a normal clock counter-clockwise, but then wouldnt it show the right hour 4 times in a day rather than 2 times a day? (6 AM, 6PM, 12 AM, 12PM) A Mmre original answer but not really practical or probably anywhere near what you were looking for would be to program a digital clock to count at the normal rate, but only go up to 4 hours and run that in reverse. This would give the following: 4 3 2 1 4 3 2 1 4 3 2 1 4 3 2 1 4 3 2 1 4 3 2 1 4 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 which only hits the right hour twice in one day. edit: i like curr3nt's 2nd answer better :-) Edited January 21, 2011 by Tribbs083 Quote Link to comment Share on other sites More sharing options...
0 araver Posted January 21, 2011 Report Share Posted January 21, 2011 Not sure if that's what you're thinking, but If it's a digital clock (24h) and you turn it upside down, it only shows the 00:00 and 11:11 correctly (the rest is mostly gibberish). If it's an analog clock, and you turn it upside down, then it gets weirder, but I think only 6 o'clock is perfectly symmetrical. Which is also twice in a day. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 21, 2011 Report Share Posted January 21, 2011 (edited) Make it run backwards? As already ,mentioned, this method by itself gives 4 correct readings. It needs to be improved to get rid of 2 of the solutions. backwards would make it correct at 6 and 12. Make the broken clock go back one second then repeat forward 2, back 2. broken correct 0:00:00 0:00:00 23:59:59 0:00:01 0:00:00 0:00:02 0:00:01 0:00:03 0:00:00 0:00:04 23:59:59 0:00:05 0:00:00 0:00:06 0:00:01 0:00:07 ... 23:59:59 11:59:57 0:00:00 11:59:58 0:00:01 11:59:59 0:00:00 12:00:00 23:59:59 12:00:01 0:00:00 12:00:02 0:00:01 12:00:03 with 0 being the same as 12. Correct, although by no means practical. Not sure if that's what you're thinking, but If it's a digital clock (24h) and you turn it upside down, it only shows the 00:00 and 11:11 correctly (the rest is mostly gibberish). If it's an analog clock, and you turn it upside down, then it gets weirder, but I think only 6 o'clock is perfectly symmetrical. Which is also twice in a day. Digital 22:22 and 20:02 (at least) are also valid Analog... I don't see any match with the real time, maybe I misunderstand the explanation... Edited January 21, 2011 by Kornrade Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 22, 2011 Report Share Posted January 22, 2011 make the clock 144min later or ealier than the correct one? Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 22, 2011 Report Share Posted January 22, 2011 Just freeze the minute and hour hand at any given time and let the seconds hand run Quote Link to comment Share on other sites More sharing options...
0 dark_magician_92 Posted January 22, 2011 Report Share Posted January 22, 2011 How can you make a clock work at the normal rate (of one second per second) but only show the right hour exactly 2 times per day? by moving it ahead of time before the time of observation by 12 hours, i.e. it will show 12 noon at 12 midnight and vice versa and since we dont use am and pm with 12:00 it will be correct twice a day Quote Link to comment Share on other sites More sharing options...
0 araver Posted January 22, 2011 Report Share Posted January 22, 2011 Digital 22:22 and 20:02 (at least) are also valid Analog... I don't see any match with the real time, maybe I misunderstand the explanation... Digital - Yeah, not upside down. Mirroring makes 2 look like 5 and 5 look like 2. My bad. Mirroring is a little harder to arrange, but that should only leave 00:00 and 11:11. Analog - I was thinking of 6 o'clock and ignoring any difference between hour hand and minute hand. Nevermind. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 22, 2011 Report Share Posted January 22, 2011 (edited) make the clock 144min later or ealier than the correct one? Why would this work? What times are shown correctly? Just freeze the minute and hour hand at any given time and let the seconds hand run I would not consider the clock running at a normal rate if one or two hands were frozen (... but it's a matter of personal opinion) by moving it ahead of time before the time of observation by 12 hours, i.e. it will show 12 noon at 12 midnight and vice versa and since we dont use am and pm with 12:00 it will be correct twice a day If PM/AM is not used at all, then it will show the correct time. If the conventions are used for the purpose of avoiding confusion, then it is only fair to add noon/midnight after 12:00 to differentiate the two cases as well. I personally find it inconsistent to differentiate between 9:00 AM/PM, but not differentiate between 12:00 noon/midnight... Digital - Yeah, not upside down. Mirroring makes 2 look like 5 and 5 look like 2. My bad. Mirroring is a little harder to arrange, but that should only leave 00:00 and 11:11. Analog - I was thinking of 6 o'clock and ignoring any difference between hour hand and minute hand. Nevermind. Mirroring still preserves the 10:01 as valid (or if you discard it because of asymetry related to ":", then 11:11 should also be discarded because of the same reason) Anyway, good tries everyone! Edited January 22, 2011 by Kornrade Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 22, 2011 Report Share Posted January 22, 2011 There's no doubt a way to do it involving time zones, i.e., flying into a different time zone at the right moment(s). Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 22, 2011 Report Share Posted January 22, 2011 just remove all the numbers but the 12. Quote Link to comment Share on other sites More sharing options...
0 fabpig Posted January 22, 2011 Report Share Posted January 22, 2011 (edited) swapping the hour and minute and second hands somehow Edited January 22, 2011 by fabpig Quote Link to comment Share on other sites More sharing options...
0 fabpig Posted January 22, 2011 Report Share Posted January 22, 2011 I entered the above on the spur of the moment. Now I think a bit more, if tou switch the hour and minute hands, the time would only be correct at 12. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 22, 2011 Report Share Posted January 22, 2011 set the clock to run counter-clockwise Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 22, 2011 Report Share Posted January 22, 2011 In stead of using a regular 12 hour analog clock, use a 24 hour analog clock, and have it run backwards. Time between the two times it is right is 12 hours. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 23, 2011 Report Share Posted January 23, 2011 Let it wind down, remove te battery, or pull the plug. A stopped clock will show the correct time twice a day Quote Link to comment Share on other sites More sharing options...
0 fabpig Posted January 23, 2011 Report Share Posted January 23, 2011 How can you make a clock work at the normal rate (of one second per second) but only show the right hour exactly 2 times per day? A stopped clock isn't working as per OP Nobody has yet said HOW to make a clock go backwards.... If switching the hands as in my reply above won't work due to different fittings, then break the minute hand to make it smaller then the original hour hand........ Quote Link to comment Share on other sites More sharing options...
0 Guest Posted January 24, 2011 Report Share Posted January 24, 2011 I dont think this is what you are seeking, but here goes: Take an analog clock and put it on a satellite going counter to the rotation of the earth, at exactly the same speed. The satellite would be in the wrong time zones except 12 and 24 hours later, and multiples thereof. Note that this only works with a 12 hr clock, because when you are 180 degrees from where you started, you will be off by 12 hours. Quote Link to comment Share on other sites More sharing options...
0 bhramarraj Posted September 14, 2011 Report Share Posted September 14, 2011 Just rotate the dial of clock so that 6 looks like 9 (after going to the top) Set the hour hand at 9 at top of the clock (originally 6) and minute and second hand at 12 down the clock. Start the watch exactly at 9 O' clock. This watch will show right time every 12 hrs only. Quote Link to comment Share on other sites More sharing options...
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How can you make a clock work at the normal rate (of one second per second) but only show the right hour exactly 2 times per day?
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