Greetings, dear guests and subscribers of my channel!
I wrote an article and mentally moved 20 years ago ...
At that time, I was still very much fond of orienteering and tourism, traveled far and wide throughout the Rostov region. And, today, I will tell you about three beautiful ways to determine the height of objects that are either nearby, or far from you, but within sight and each of the methods, if you follow the rules, gives a fairly accurate result.
So the first way: Reflection
First: pouring water on the ground!
This is not a joke :-), you need to pour water in front of you into any hole, creating a small puddle - a "mirror". In addition to water, you can use other handy items: glass, the flat part of a knife blade, a CD, etc.
There is a law in physics - light refraction lawwhere, in a homogeneous environment, the angles of incidence and reflection of light are equal. Therefore, it is enough to catch the highest point of the object with a glance in the water mirror.
The whole point of determining the height lies in the geometric laws of similar triangles and if two angles in they are equal, then the triangles are similar, respectively, the equality of the similarity coefficient of the ratio parties:
X / x = Y / y, so the height of the Y object is: Y = (X * y) / x, where:
y - human height.
The question may arise "How to fix point O?" Answer: any stone, stick or coin!
Method two: Shadow
The essence of this method is the same - similar triangles, but created by casting shadows from objects. I hope that in my photo the fact that the triangles are similar does not raise any questions - all angles are equal :-)))
Here it is enough to place any object vertically, to measure the height and length of its shadow. I installed a peg.
Further, by the aspect ratio, get the desired height:
Y = (X * y) / x
The third method: Determining the height from the photo
If you have an object with you, the size of which you know, then you can install it in the immediate vicinity of the object - take a picture.
Then, in the photo editor on your phone, you can postpone equal segments to the highest point of the object and multiply the height of your subject by the number of segments.
I took a ruler with a total length of 31 cm. I put aside 9 whole segments and another 1/3. Now, we calculate: 31 * 9.3 = 288.3 cm. or 2 m 88 cm.
As a bonus:
1. Item at hand
We take in our hands any elongated object, we combine its top with the upper point of the object (in my case, a support power transmissions), and fix the lower point with a thumbnail (this point will later serve as a point rotation).
Now, turn the object 90 degrees. and postpone the distance. The top of the object will point to a point that is the projection of the height onto the horizontal plane. All that remains is to measure.
2. How do you know the depth of the well? Or maybe - the tree on which you sit :-)))
We take out the phone, open the "stopwatch" application, press "Start" and at the same time let go ...
... no, not a telephone, but something that is heavy nearby: a coin, a pebble or some object that will not be carried away by the wind in free fall.
The path covered by the body is:
But, taking the acceleration of gravity as 9.8 m / sq. S, we get a simplified formula:
where t is the time measured by the stopwatch.
I hope it was interesting, informative and you will definitely put your finger on down up :-))) Thank you!
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