Long ago, people decided to divide the day into units called hours. They chose 24 as the number of hours in one day. Why is 24 a more convenient choice 23 or 25?
24 is more easily divided into parts
... divisible by 2, 3, 4, 6, 8, and 12
23 is prime
... no factors other than itself and one
25 is only divisible by 5
The choice to divide the day into 24 hours was not arbitrary; it was influenced by various factors and historical reasons. Here's why 24 hours proved to be a more convenient choice compared to 23 or 25.
1. Divisibility: One significant advantage of choosing 24 hours is that it is highly divisible. It can be evenly divided by 2, 3, 4, 6, 8, and 12. This divisibility property makes it easier to divide the day into smaller units such as minutes and seconds.
2. Ancient Mesopotamian Numerology: The concept of dividing the day into 24 hours can be traced back to ancient Mesopotamia. The Mesopotamians had a numerology system based on the number 60, known as sexagesimal. They divided the circle into 360 degrees, and each degree into 60 minutes. This sexagesimal system influenced the division of time, leading to 24 hours per day and 60 minutes per hour.
3. Astronomical Alignment: The choice of 24 hours aligns with the Earth's rotation and its alignment with the stars. As the Earth spins once on its axis in approximately 24 hours, this division allows a convenient correspondence between the hours marked on a clock and the Earth's rotation.
4. Historical Adoption: The 24-hour system was adopted and standardized by various civilizations throughout history, including the Egyptians, Greeks, and Romans. This historical continuity contributed to the widespread use and acceptance of the 24-hour system.
In contrast, if we were to choose 23 hours, the divisibility property would not be as favorable. It would only be divisible by 1 and 23. Similarly, if we were to choose 25 hours, the divisibility is not as convenient. It would only be divisible by 1, 5, and 25. These factors make 24 a more practical and widely accepted choice for dividing the day into units called hours.