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Degrees and minutes
- Thread starter Deny1950
- Start date
It works kind of like time. There are 360 degrees in a circle, 60 minutes in each degree, and 60 seconds in each minute. That is commonly referred to as the "DMS" system. There is also the "DD" system, meaning Decimal Degrees. 45.5° is the same as 45°30' for example. Just two ways to express the same thing.
It's just an older way to handle fraction parts of a degree. It's base 60 meaning numbers are counted from 0 to 59. Same goes for seconds.
Say you 59.265 degrees. It would be 69 degrees + .265 x 60 (= 15.9). So far you have 69 degrees, 15 minutes. Now take 0.9 x 60 (=54).
The total answer is 69 degrees, 15 minutes, 54 seconds.
You can convert the other way by dividing the minutes and seconds by 60 and adding the numbers together.
Think of the hour hand on a clock. As the seconds tick, the minute hand moves slightly and so does the hour hand. This is just a way to represent the incremental movement of the hour hand based on the intermediate locations of the minute and second hands.
Ray
EDIT: Let's say you had a wall clock that was numbered 0-359 (instead of 1-12). If you wanted to represent 56.265 degrees, you would move the hour hand to 59 then, advance the minutes hand to 15 and the second hand to 54. The extra motion of moving the minute and second hand would cause the hour hand to move forward a little bit -and it would be at 59.265 degrees.
I was really happy when they stopped doing it this way when calculators became common!
Say you 59.265 degrees. It would be 69 degrees + .265 x 60 (= 15.9). So far you have 69 degrees, 15 minutes. Now take 0.9 x 60 (=54).
The total answer is 69 degrees, 15 minutes, 54 seconds.
You can convert the other way by dividing the minutes and seconds by 60 and adding the numbers together.
Think of the hour hand on a clock. As the seconds tick, the minute hand moves slightly and so does the hour hand. This is just a way to represent the incremental movement of the hour hand based on the intermediate locations of the minute and second hands.
Ray
EDIT: Let's say you had a wall clock that was numbered 0-359 (instead of 1-12). If you wanted to represent 56.265 degrees, you would move the hour hand to 59 then, advance the minutes hand to 15 and the second hand to 54. The extra motion of moving the minute and second hand would cause the hour hand to move forward a little bit -and it would be at 59.265 degrees.
I was really happy when they stopped doing it this way when calculators became common!