OUTDOOR TRIGONOMETRY

应用三角容易估计距离为战士呢。

Do you like exploring the country? Do you like outdoor sports? Sometimes you need to know the distance to another people group, to a far away mountain, to a house or the distance to a sailing boat in a competition.

You don't have a telemeter in your hands, but you know you can apply trigonometry easily to estimate that distance in the same way as soldiers do with their targets.

You have to extend your arm and estimate the angle to the target with your fingers as it is shown in the figure (in angular mils).

You have to estimate the size of the object (p.e. a 3 floor house is 3 x 3 = 9 m height).

You have introduce data in your device touching on the yellow and blue bands, to the left to introduce lower values or to the right to introduce higher values.

Below, in red, over a green band you can see the estimated distance.

The application contain a brief explanation. To do the estimation you use the tangent of the angle to the target which is the opposite side of the triangle (size of the target) divided by the other side of the right triangle (the distance to the target).