Why 1 degree corresponds to 60 min?

  • Context: High School 
  • Thread starter Thread starter ftnunosilva
  • Start date Start date
  • Tags Tags
    Degree
Click For Summary

Discussion Overview

The discussion centers around the relationship between degrees and minutes in angular measurement, specifically why 1 degree corresponds to 60 minutes of arc. Participants explore the historical and logical foundations of this division, as well as the distinction between minutes of arc and minutes of time.

Discussion Character

  • Conceptual clarification
  • Historical
  • Debate/contested

Main Points Raised

  • One participant questions why 1 degree corresponds to 60 minutes, suggesting it should relate to the 4 minutes it takes for the Earth to rotate 1 degree.
  • Another participant clarifies that the "minute" in this context refers to minutes of arc, not minutes of time, stating that 1 degree equals 60 minutes of arc.
  • A participant discusses the historical context of the 60 system, noting its divisibility and historical use by the Sumerians and Babylonians, while also mentioning the complexity of historical measurement systems.
  • There is a humorous remark about the universality of the base 10 system, which does not explain the prevalence of the 12 and 60 systems.

Areas of Agreement / Disagreement

Participants express differing views on the logical basis for the division of degrees and minutes, with some agreeing on the distinction between minutes of arc and time, while others remain confused about the relationship.

Contextual Notes

The discussion highlights the historical complexities and arbitrary nature of measurement systems, with no consensus on the underlying reasons for the specific choice of 60 minutes in angular measurement.

ftnunosilva
Messages
4
Reaction score
0
I have a doubt: considering it takes 24h to a complete rotation of earth, why 1º corresponds to 60 min? It should be 4 min...

Can you help me?

Thanks you

Nuno Silva
 
Mathematics news on Phys.org
So, this "minute" isn't the 1/60 of a hour?
 
ftnunosilva said:
So, this "minute" isn't the 1/60 of a hour?
No.

Don't confuse minutes of arc (a measure of angle) with minutes of time.

1 degree = 60 minutes of arc.
 
Thank you very much... After reading Around the World in Eighty Days, I became all mixed up! :-)
 
These things are not based upon logic, so much as history. Even to very recent times, the English used 12 pence to a shilling, 20 shillings to a pound. This complicates arithmetic, of course, but bookkeepers easily mastered it.

A reason for 60, like 12, is that it is easily divisible. So that in early times, it was used to facilitate making change and dividing up products. (Farmers, even in this country, favor the 12 makes a dozen eggs.) The Sumerians, and then the Babylonians, used the 60 system, but for hours it was 12 in the day and 12 at night. (This is not exactly the same as the 24 hour system, since some days are longer than others.) Where the Sumerians got the idea of 12 hours of daylight, is really hard to say.

I once hear a joke, "How many fingers do the flying saucer people have counting both hands?"

Answer: 10, we just don't know what base they use.

However, that idea, the universality of 10, hardly explains the 12 and 60 system.
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 34 ·
2
Replies
34
Views
4K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K