Why does a circle have 360 degrees instead of 100?

[konartist]

Does anyone know why there is 360 degrees in a circle? Why not 100 for simplicity sake?

 

[moose]

3600 seconds in an hour.

EDIT: Maybe I should state that this is only an educated guess... Kind of...

EDIT2: Actually, it's a complete guess.

 

[arildno]

Does anyone know why there is 360 degrees in a circle? Why not 100 for simplicity sake?

It's a leftover from Babylonian maths, I think.

Note that 360 has a heck of a lot more divisors than 100; thus, one might argue that it is simpler to use 360 than 100 (there is, in however, a somewhat used system of measuring angles that uses 400 units in the full circle).

 

[FredGarvin]

The Sumerians watched the Sun, Moon, and the five visible planets (Mercury, Venus, Mars, Jupiter, and Saturn), primarily for omens. They did not try to understand the motions physically. They did, however, notice the circular track of the Sun's annual path across the sky and knew that it took about 360 days to complete one year's circuit. Consequently, they divided the circular path into 360 degrees to track each day's passage of the Sun's whole journey. This probably happened about 2400 BC.

From here:
http://www.wonderquest.com/circle.htm

However, this source states it a bit differently: http://mathforum.org/library/drmath/view/59075.html

the ratio of the perimeter of a regular hexagon
to the circumference of the circumscribed circle equals a number which in
modern notation is given by 57/60 + 36/(60^2) (the Babylonians used the
sexagesimal system, i.e., their base was 60 rather than 10).

The Babylonians knew, of course, that the perimeter of a hexagon is
exactly equal to six times the radius of the circumscribed circle, in fact
that was evidently the reason why they chose to divide the circle into 360 degrees

 

[Jonny_trigonometry]

didn't the Babylonians use a base 60 number system?

 

[BobG]

Sexagesimal is base 60. Actually, the Babylonians used a dual base system. Base 60 was the primary base with 10 as the secondary base (another example of a dual base system would be the Roman numeral system which has 10 as a primary base and 5 as a secondary base).

With the number of degrees approximately equal to the number of days in a year, the position of the stars shifts about 1 degree per night - a handy thing to know if you navigate by the stars as the Babylonians did.

As constructed, angles in degrees are compatible with time. The only difference is that there are 15 degrees per hour (that's the Earth's approximate rotation rate).

 

[heman]

a similar question can be

"why are there are 32 bit operations most in computer.."

 

[FredGarvin]

a similar question can be

"why are there are 32 bit operations most in computer.."

Everything in computers is based on the binary system. $$2^5 = 32$$. You also see 64 bit and 128, etc...Currently 32 bit is the norm. Soon it will progress (if things keep going the way they are).

 

[arildno]

And the answer is analogous:

Due to the regular rise&fall of the Nile, it was convenient for the ancient Egyptians to make 32 bit computers in order to estimate the optimal base angle in the construction of their pyramids.

 

[Chi Meson]

And the answer is analogous:

Due to the regular rise&fall of the Nile, it was convenient for the ancient Egyptians to make 32 bit computers in order to estimate the optimal base angle in the construction of their pyramids.

I did not know that!

 

[konartist]

Another thing I heard was that Einstein failed math 3 times! I can't believe it.

So many interesting things about math!

 

[FredGarvin]

And the answer is analogous:

Due to the regular rise&fall of the Nile, it was convenient for the ancient Egyptians to make 32 bit computers in order to estimate the optimal base angle in the construction of their pyramids.

What's the connection between the Nile and 32 bit? High tide - low tide?

 

[Integral]

What's the connection between the Nile and 32 bit? High tide - low tide?

I think it had more to do with the mosquito population.

 

[Phobos]

I seem to recall hearing that there was some spiritual significance (Babylonian?) to the number 12 too (easily divides into 360).

 

[RandallB]

I seem to recall hearing that there was some spiritual significance (Babylonian?) to the number 12 too (easily divides into 360).

More to do with the number base (Sexagesimal is base 60) BobG was talking about. Six of those fit the year fairly well.
And a base 60 divides in so many handy ways - 2 3 4 5 6 10 12 15 20 30
Gee - think it could compete with metric?

 

[topsquark]

Hey, using 360 degrees is FAR better than using $$2 \pi$$ radians!

-Dan

 

[Danger]

Due to the regular rise&fall of the Nile, it was convenient for the ancient Egyptians to make 32 bit computers in order to estimate the optimal base angle in the construction of their pyramids.

I was totally unaware that the ancient Egyptians even had computers, never mind 32-bit ones. Did they look anything like this?















http://img82.imageshack.us/img82/188/cadbcpfcopy9la.jpg

 

[BobG]

I was totally unaware that the ancient Egyptians even had computers, never mind 32-bit ones. Did they look anything like this?

I was always under the impression that they only had 20 bit computers.