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Make a right triangle, with the sloper as the hypotenuse. One apex of
the triangle is the higher sloper wire end. Go straight downward from there 34 - 8 = 26 feet to form the second side of the triangle. Then go from there straight horizontally to the lower sloper wire end to form the third side. The following isn't to scale, but it should give you the idea. View it with your browser set to a fixed, not porportional, font: / / | sloper / | 73' / | 26' / | / | /__A_______________| The answer to your question requires basic trigonometry, usually taught in high school in the U.S., so 6th grade math won't quite cut it. Of course, you could draw it to scale on a piece of paper and use a protractor to determine the angle, and that would be adequately accurate for most purposes. Angle A is the angle the sloper is tilted upward or downward from horizontal. The sine of an angle in a right triangle = the length of the side opposite the angle divided by the length of the hypotenuse, which for angle A is 26/73. So we know that the sine of A = 26/73 = 0.356. In this day and age, the way to find the angle once we know its sine is to use a (scientific) pocket calculator. The function we want is "arcsin", "ASIN", "inverse sine", or "SIN^-1", all of which mean "the angle whose sine has this value". I notice that the calculator which comes with my XP operating system (in the Accessories folder) has this function. If you have one in your operating system, first make sure the "Degrees" selection is made in the upper right (assuming you want the answer in degrees). Then enter .356 into the calculator, check the Inv box (so you'll get the inverse sine), and finally click the "sin" button. The answer, with a ridiculous number of digits, is about 21 degrees. You don't have to take a course in trig to learn and use the basic functions sine, cosine, and tangent, which are just ratios of the various sides of right triangles. (The cosine is the length of the adjacent side divided by the length of the hypotenuse, and the tangent is the length of the opposite side divided by the length of the adjacent side.) With that knowledge and an inexpensive (or free) calculator, you can easily solve problems like this. Roy Lewallen Zachary Taylor wrote: I have a sloper that is 73 feet long. The high end is 34 feet high, and the low end is 8 feet high. What angle is the antenna? It's a shame I can't figure out something I should have learned in the 6th grade; but I don't know how to set the problem up. Thanks, Zack |
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