24 hour how many minutes

Ask Question. Asked 8 years, 8 months ago. Active 6 years, 7 months ago. Viewed 48k times. Each of these can be rotated 4 ways, by 0,1,2 or 3 places. For example : In which case only 1 and 2 are valid 24 hour times. This is not a homework question. Cris Stringfellow. Cris Stringfellow Cris Stringfellow 1 1 gold badge 6 6 silver badges 22 22 bronze badges. Oh wait, you might be thinking of this as digits instead? Add a comment. Active Oldest Votes. That is SO weird. Awesome answer joriki!

I ran your code but have no looked at it in detail -- could you possibly briefly describe the code idea and it gives as you say. The code loops over all times, creates a four-digit string for each, loops over the four possible rotated strings, counts the number of rotated strings that represent valid times, and remembers all strings seen so far. He also devised a system of longitude lines that encompassed degrees and that ran north to south, from pole to pole. In his treatise Almagest circa A.

Each degree was divided into 60 parts, each of which was again subdivided into 60 smaller parts. The first division, partes minutae primae, or first minute, became known simply as the "minute. Minutes and seconds, however, were not used for everyday timekeeping until many centuries after the Almagest.

Clock displays divided the hour into halves, thirds, quarters and sometimes even 12 parts, but never by In fact, the hour was not commonly understood to be the duration of 60 minutes. It was not practical for the general public to consider minutes until the first mechanical clocks that displayed minutes appeared near the end of the 16th century. Even today, many clocks and wristwatches have a resolution of only one minute and do not display seconds. Thanks to the ancient civilizations that defined and preserved the divisions of time, modern society still conceives of a day of 24 hours, an hour of 60 minutes and a minute of 60 seconds.

Advances in the science of timekeeping, however, have changed how these units are defined. Seconds were once derived by dividing astronomical events into smaller parts, with the International System of Units SI at one time defining the second as a fraction of the mean solar day and later relating it to the tropical year.

This changed in , when the second was redefined as the duration of 9,,, energy transitions of the cesium atom. Interestingly, in order to keep atomic time in agreement with astronomical time, leap seconds occasionally must be added to UTC.

Thus, not all minutes contain 60 seconds. A few rare minutes, occurring at a rate of about eight per decade, actually contain Already a subscriber? Sign in. Thanks for reading Scientific American. Create your free account or Sign in to continue. See Subscription Options. Discover World-Changing Science. References Time's Pendulum. Time Conversion ». Facebook Twitter.

Recent Comments germanshephard. T h a n k s Thanks, helped me, I wrote it down so I won't forget, thanks again! Hello Everyone This website helped to a certain extent. Josie brown I love min and hours.

Rainbow pup Helpful but can you do the whole number and a fraction in minutes. Durosinmi Etti Matilda very very good and essential for me to learn and it guide me when am doing my assignment. Nasimane Can you please add the formulas too,would truly appreciate that. Ruby This really helped me with my homework assingment!