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05242006

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i have an odd question
this deals with navigation, maybe?
any info would be appreciated.

05242006


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The numbers in (parentheses) are radians .... where the circumference of the circle is 2π radians. 180 degrees is π radians. 90 degrees = π/2 radians, etc.
Its a 'trigonometry' plot in radians as well as degrees.

05242006

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Quote:
Originally Posted by RichH
The numbers in (parentheses) are radians .... where the circumference of the circle is 2π radians. 180 degrees is π radians. 90 degrees = π/2 radians, etc.
Its a 'trigonometry' plot in radians as well as degrees.

thanks rich
can you tell me where? or is that not possible?

05242006


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No, they're not radians
The numbers in the parenthesis is the tangent of the angle (x/y). The give away was the very top item (Tan = 0) right above the 0 degree mark. Unfortunately, there is also a mistake, the tangents of 90 and 270 degrees is infinity. Plug the angles into your calculator and hit TAN, you'll see the same answers.
Boy, instead of something something useful, I really wanted to say "and here's your odd answer: "pbpbbp gaaa wubbida wubbida wubbida boiiing!"
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Last edited by duffer1960; 05242006 at 08:13 AM.

05242006

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Quote:
Originally Posted by duffer1960
The numbers in the parenthesis is the tangent of the angle (x/y). The give away was the very top item (Tan = 0) right above the 0 degree mark. Unfortunately, there is also a mistake, the tangents of 90 and 270 degrees is infinity. Plug the angles into your calculator and hit TAN, you'll see the same answers.
Boy, instead of something something useful, I really wanted to say "and here's your odd answer: "pbpbbp gaaa wubbida wubbida wubbida boiiing!"

lol, thanks for the reply.
well seeing that i have no idea what this all means you could through in two boiings at the end and i wouldnt know the difference.
this is some kind of navigation key? unsure. 360 is north, maybe. there is one other direction and that is 108 could be north.
i was thinking after researching the net that these tangents were derived using a sextant?

05242006

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Quote:
Originally Posted by duffer1960
The numbers in the parenthesis is the tangent of the angle (x/y). The give away was the very top item (Tan = 0) right above the 0 degree mark. Unfortunately, there is also a mistake, the tangents of 90 and 270 degrees is infinity. Plug the angles into your calculator and hit TAN, you'll see the same answers.
Boy, instead of something something useful, I really wanted to say "and here's your odd answer: "pbpbbp gaaa wubbida wubbida wubbida boiiing!"

when you say the tangent of 90 and 270 are infinite what do you mean? are you speaking of the (0) if so, 180 has a tangent of (0) would that mean its infinite also?

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In navigation (ignoring the difference between true and magnetic), generally speaking, 360 (or 000) is north, 90 is east, 180 is south, and 270 is west. Southeast would be halfway between 90 and 180135so 108 is East Southeast (ESE).

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Quote:
Originally Posted by SailinJay
In navigation (ignoring the difference between true and magnetic), generally speaking, 360 (or 000) is north, 90 is east, 180 is south, and 270 is west. Southeast would be halfway between 90 and 180135so 108 is East Southeast (ESE).

that was my assumption. the only thing is there is another part of the key that shows 108 as north. in others words a compass points to north at 108 degrees. so it shows magnetic north at 360 and in another part of the puzzle it shows 108 as magnetic north. yes this is a puzzle of which i have no idea what it is for, yet. we figured that it was some type of navagational tool used for spherical triginometry which from what i understand was used for celestial navigation.
thanks again for all the input.

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douggiestyle:
That diagram has nothing to do with navigation . . . IMO. Someone, for some reason, wanted to divide a circle along it's radians into 10 equal parts. So, drew the diagram you posted.
Did you find it in a pizza parlor?
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05242006


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OW....
Duffer you are right ..... definitely a tangent function and with errors at 270 and 90 degrees  should be infinite value instead of 0
Douggie
A tangent is defined as the opposite side length divided by the adjacent side length with reference to the angles and 'sides' as described by the geometry of the illustration, etc. This is referenced to a circle with "1 unit" (1 ft., 1 mile, 1 mm, etc.) for reference. Tan(angle) = (opposite side)/adjacent side) .... its just a trigonometry 'definitiion'. The numberic values are the ratio of the 'sides' of the triangle that fits 'inside' the circle and as defined by the radius of the circle being at the 'angle' of radius of circle.
For the tangent at either 90 or 270 being 'infinite' .... because the 'y' componet of the 'triangle' described by its projection on the x/y axis (x=0, y=0 at the center of the circle) and with the radius of the circle being 1 ... is: 1 divided by zero and any number divided by zero is infinity.
Tan = x divided by y = x / y; and for 90 degrees, x = 1 but y = 0; so 1/0= infinity.
Trigonometry is sooooooooo easy to explain by drawing the damn stuff ..... and so confusing when describing solely by 'words'.
The basic concepts of trigonometry are so extremely simple but 'words' only makes it 'confusing'.

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