Ruby Martis: One task they need to do is chop down trees to clear space for a new feature It is necessary for landscape architect to know the height of a tree before cutting it down, so they can work out where the right place to bring it down is - they want to bring the tree down without having it fall on property. An easy way of finding the height of a tree without climbing it is to use trigonometry, and a device known as a clinometer. This site does a good job of describing the clinometer: http://www.countrysideinfo.co.uk/wet_wood_survey_2...The clinometer tells you the angle of elevation you need to look at to see the top of the tree ... you look at the top of the tree through two sighting points, all the while squeezing the trigger. When you have it lined up correctly, release the trigger and gravity makes the arrow point straight down. You can then look at where the arrow's pointing - that gives you the angle of elevation. In the picture, you can see from the scale a! t the bottom, that the clinometer is pointed at an angle of around 15 degrees.We see from the table on the site that from a distance of 8 metres away from the base of the tree, if the angle of elevation to the top of it is 54 degrees, and the eye-level of the person taking the measurement is 1.8 m, then the tree is 12.8 m tall. How did they get that figure? Well, let's replicate this calculation. A little geometry (I'd draw you a diagram but I don't have access to a scanner right now, maybe later if I get around to it) shows the height of the tree above eye-level in metres is 8tan54 (Get out your calculator!) = 11.01 m. Adding the height of the measurer's eye level results in 12.8 m. Obviously this method works best on flat land but even in hilly areas. it is usually possible to do this across the hill, so it's still done by someone standing at the same height as the base of the tree.That's one application of trigonometry in landscape architecture. The other is measuring th! e height of a slope.You want to construct buildings and parkin! g lots on flat terrain if possible. You should know that slope is given by 'rise over run', in other words the change in height divided by the change in lateral distance. In a flat terrain this slope will be quite low, and can be expressed as slope as you see it in a y = mx + c graph you typically see almost every day in maths class as a 14/15 year old, or as an angle.Typically, ground with slope less than 5 degrees is regarded as flat, ground with slope between 5-15 degrees is regarded as medium and steeper than 15 degrees is regarded as steep, and the use of such terrain depends on the steepness. Have a look at pages 79 and 80 of http://books.google.co.nz/books?id=mKjCPPef7jYC&pg... for more info.EDIT: I have now drawn a diagram for the tree scenario: http://s873.photobucket.com/albums/ab299/kiwijoey/...Note that trigonometry is a study of the geometry of right triangles, at the basic level it is first introduced. Well, you have a right triangle here, it's drawn in red.No! te the difficulty the measurer has in seeing where the tree top is through some of the foliage on the front side. I personally believe 8 m is too close to take the measurement, they should have done it from about 25 m away, where the angle would be flatter (about 24 degrees) and this would be less of a problem....Show more
Nikita Schroepfer: you want to carry close your "Gozintas" you understand, "2 gozinta 4" and "3 gozinta 9" heavily, all math is reliable math for technical careers. Load up on airplane (2d) and round (3D) geometry, algebra, and trig. Calculus possibly gained't do a lot for you rapidly, notwithstanding this is going to stretch your concepts and coach you to imagine abstractly and deeply. depart the easy practise to the liberal arts applicants, and study technological understanding and MATH in case you desire a lengthy, fufilling, and FINANCIALLY worthwhile occupation. Maranatha...Show more
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