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Morris Dovey Morris Dovey is offline
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Default angles: trig help

Joe wrote:
| I want to double check some wedges I've made for angled cuts. In a
| 24" long wedge, how much gain on the square corner is there for
| each degree of angle?
|
| I know the method is rattling around back there amongst the unused
| and as yet unkilled brain cells but I can't seem to come up with it.
|
| Thanks to the more mathmatically inclined.

It's not the same for each degree of angle (the gain going from 0 to 1
degree is a lot larger than the gain when you go from 88 to 89).

Since the tangent of an angle (a) is equal to the rise (y) divided by
the run (x=24), you can calculate:

tan(a) = y / 24

y = 24 * tan(a)

If a1 is your starting angle then

y1 = 24 * tan(a); and
y2 = 24 * tan(a+1)

and the gain for that 1 degree difference is

y2 - y1 = 24 * (tan(a+1) - tan(a))

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto