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#1
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angles: trig help
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. jc |
#2
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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 |
#3
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angles: trig help
Morris Dovey wrote:
| 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). I think I said that backward. :-( larger -- smaller -- Morris Dovey DeSoto Solar DeSoto, Iowa USA http://www.iedu.com/DeSoto |
#4
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angles: trig help
I am not going to attempt ASCII art.
If by the "square corner" you mean the two sides of a right angle triangle which are orthogonal (90 degree angle between these sides, then the formula is Height = Length * Tangent(opposite angle). For Length = 24 inch and opposite angle = 1 deg, then Height = 0.418922 If you have MS Excel, then you can enter a formula Cell for Height = =Cell for Length*TAN(RADIANS(Cell for angle)) For some strange reason MS designed Excel to use RADIANS in angle functions instead of degrees where 180 deg = PI Radians. Dave Paine "Joe" wrote in message . .. 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. jc |
#5
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angles: trig help
As Morris Dovey warned in a separate message, the height is not linear for
each degree. Hence you do need to use the formula. Dave Paine "Tyke" wrote in message ... I am not going to attempt ASCII art. If by the "square corner" you mean the two sides of a right angle triangle which are orthogonal (90 degree angle between these sides, then the formula is Height = Length * Tangent(opposite angle). For Length = 24 inch and opposite angle = 1 deg, then Height = 0.418922 If you have MS Excel, then you can enter a formula Cell for Height = =Cell for Length*TAN(RADIANS(Cell for angle)) For some strange reason MS designed Excel to use RADIANS in angle functions instead of degrees where 180 deg = PI Radians. Dave Paine "Joe" wrote in message . .. 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. jc |
#6
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angles: trig help
"Joe" wrote in message . .. 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. jc Assuming the 24" side is included between the right angle and the angle to be incremented, and the 24" side and the 'gain' side are at right angles to each other: Gain in inches = 24*tangent(incremented angle). For some angles: 1 deg- .4189516" 2 deg- .8380985 15 deg - 6.4307806" 22.5 deg- 9.5941125" 30 deg - 13.8564061" 45 deg - 24.0000000" 89 deg- 1,374.9590791" etc..... Using Windows calculator makes the computation easy once you know the equation. Tin Woodsmn Happy New Year to all of the Wreckers.... |
#7
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angles: trig help
In article ,
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. jc What do you mean by "gain" ? If you mean, for a right triangle with angel A between the hypotenuse and a 24" side, that the "gain" is the length of the side opposite angle X, then the change in the length of that side is not a linear function wrt the angle X. However, it will be equal to 24 X sine(A) -- Often wrong, never in doubt. Larry Wasserman - Baltimore, Maryland - |
#8
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angles: trig help
OOPS, maybe a little doubt would be good on this one.
G/HYP does = SIN X, but you have two unknowns, since the base is fixed at 24. G = HYP*SIN X doesn't help, since we don't know the hypotenuse. As Tin said, TAN X = G/24, so G = 24 TAN X. I hope I'm not too sleepy to get this right. WL wrote in message ... In article , 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. jc What do you mean by "gain" ? If you mean, for a right triangle with angel A between the hypotenuse and a 24" side, that the "gain" is the length of the side opposite angle X, then the change in the length of that side is not a linear function wrt the angle X. However, it will be equal to 24 X sine(A) -- Often wrong, never in doubt. Larry Wasserman - Baltimore, Maryland - |
#9
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angles: trig help
In article . net,
Wilson wrote: OOPS, maybe a little doubt would be good on this one. G/HYP does = SIN X, but you have two unknowns, since the base is fixed at 24. G = HYP*SIN X doesn't help, since we don't know the hypotenuse. As Tin said, TAN X = G/24, so G = 24 TAN X. You are right, I was mixing up my sides, the tangent is correct. -- A man who throws dirt loses ground. Larry Wasserman - Baltimore Maryland - |
#10
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angles: trig help
Funny story on that subject:
On of my aspiring architectural drafters was trying to make a model of his project with a 6/12 roof slope. The roof just wouldn't work out. After lots of investigation, I found out that he had reasoned that if a 12/12 slope gives a 45 degree angle, a 6/12 should give a 22.5 degree angle. He just couldn't see my arguments to the contrary. The only way I convinced him was to ask him to draw a roof slope at 24/12, and see if it produced a 90 degree angle.... Old Guy oe" wrote in message . .. 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. jc |
#11
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angles: trig help
Thanks everyone for the help. In the original post, I neglected to mention
that I was calculating this for the first couple of degrees. I've got it now. Have a very happy and healthy New Year. jc "Joe" wrote in message . .. 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. jc |
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