Often you have to work with geometric shapes, the calculations of which are not easy to explain. If you need to find the area of a square or rectangle, then they can be conditionally divided into some parts and intuitively derive the correct formula. However, the circumference is not quite a standard object for ordinary students. Often there is a misunderstanding of this topic. Let's see what’s up.
The circle itself is formed due to two parameters: the radius and the geometric position of the center. The latter understands high school, so he is of little interest to us. But the first sets the basic properties, such as area. The circumference of the circle actually depends only on the radius and is calculated by the following formula:
L = 2PR
For the desired indicator we take L. The factor P ("Pi") is a constant. To successfully solve problems at school, it is enough to know that P = 3.14. However, it is not always necessary to substitute this value, since it is very simplified. If we are talking about large scales, it is necessary to consider a considerable number of decimal places. Therefore, in many cases, the answer in general terms is more acceptable without any rounding. Remember that the calculation of the circumference depends only on the radius. This is an indicator of how far all points of the circle are from the center. Accordingly, the larger this parameter, the longer the arc. Like conventional distance indicators, L is measured in meters. P is the radius.
In more real conditions, complicated tasks take place. For example, when the length of a circular arc is needed. Here the formula is a little more complicated. It should be understood that it is based on the basic regularity, but cuts off the portion of the length that you do not need. In general terms, it can be written as follows:
L = 2PR / 360 * n
As you can see, there is one new variable n. This is a visual designation. The entire circumference was divided into 360 degrees. Thus, it became known how many meters are 1 degree. Further, substituting the values of the desired revolution around the axis instead of the letter n, we get the long-awaited answer. Taking a single segment, we proportionally increased it n times.
Why in real life do you need to know what the circumference is? This question cannot be answered that would cover all areas of application. But to get started, let's start with a primitive clock. Knowing the radius of movement of the second hand, you can find the distance that it must go in a minute. After the path and time become known , we can find the speed with which it moves. And further only the people who are engaged in hours will go deep. If a cyclist moves along a circular track, then his travel time depends on speed and radius. You can find its acceleration. In washing machines, it also does not do without an indicator that we almost disassembled. There, the circumference is necessary for counting the revolutions (everything depends on the distance), done for a certain amount of time. In larger conditions, due to the circumference, the motion of the planets in orbits and so on is predicted.
Thus, for a clear understanding of the topic, it is necessary to remember only two formulas. This knowledge will be useful to you not only at school for good grades, but also in real life.