Ball and circle: the same geometric shapes or not? What is the difference between a circle and a ball?

Many people think that the ball and circle are the same figures. But this is not so.

Content

In science, there are the concepts of “ball” and “circle”, in connection with which the question arises whether these are the same geometric shapes or they have some differences.

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To resolve the question of the difference between the ball and the circle, it is important to understand what each figure is and to compare them. Read further.

What is a circle?

In geometry, many surface points limited by circle are called around. Its main difference is that the circle is a two -dimensional and flat figure. Formally, the circle consists of three main components:

Center
Circles
Many points located between the center and the circle

In order to clearly depict a circle on paper, you must first draw a circle with a circul, and then evenly paint over the space between the center and the circle.

The main parameters of the circle are its area and perimeter. They are calculated if the radius of the circle is known (the line connecting the center of the circle and any point of the circle) or the diameter of the circle (the segment connecting two points of the circle and drawn through the center). The main difference separating the circle from other figures similar to it is the equidistance of any point of the circle from its center and the absence of corners.

Any circle can be divided into several sectors. To do this, it is necessary to draw two radius from the circle to the circle to the circle.

What is a ball?

The ball is considered the totality of all points in the space located from the center of the ball no more than a given value. The ball is a figure of a three -dimensional measurement and is formed by a rotation of a circle or semicircle along the diameter axis. This figure consists of:

Circle center
Spherical circle
Many points between the center and the circle

The ancient Greek mathematician Euclid first described the ball as a voluminous body created as a result of the rotation of a semicircle. In ancient times, the ball was considered an ideal figure. Astronomers associated the ball with something cosmic, citing the fact that the planets are in the shape of a ball.

The main parameters of the ball are its area and volume, you can calculate them by knowing the radius or diameter. The ball, similarly to a circle, does not contain corners and any point belonging to its sphere is equidistant to the center.

In a familiar life, this figure has become widespread. A ball for billiards, a cannon core, planet Earth - everything is this figure. However, do not confuse them with spherical circles. So, a football ball, a spherical bulb or a Christmas tree toy - all these are representatives of spherical circles.

Varieties of the ball

There are two types of balls:

Open- This is a set of points in space located at a distance not exceeding the given value from its center.
Closed - This is a set of points of space located within the center of the ball and spherical circle.

Thus, the difference between them is the presence of a spherical circle.

Character characteristics

Mentioning the ball, its main characteristics are metric indicators, namely the volume of the ball, the area of \u200b\u200bthe surface of the ball and its section. In addition, there are characteristics inherent exclusively to this figure. These include the following:

If you cut the ball into two parts, regardless of the section of the section, a circle will be formed.
The ball has the largest volume among other three -dimensional figures with equal surface area.
Every two points of the ball in its diameter, it is possible to draw many circles.
Any two circles in the ball when crossing will form a line. If the diameter of such circles will coincide with the diameter of the ball, their intersection will be a line drawn through the center of the ball.
Each point belonging to the sphere of the ball is equidistant from its center.

From any ball you can get its segment, cut or sector. The segment of this figure is the object obtained when the part is cut off from it with any plane. The cut of the ball is its part obtained as a result of conducting two parallel planes through it. The segment with a cone is considered the sector, provided that its center coincides with the center of the ball.

Ball and circle: the same geometric shapes or not?

Answering the question asked, it should be concluded that the circle and ball are not the same geometric shapes. However, these figures have much in common. Any ball can be obtained by rotating the circle, and in the section of any ball you can find a circle.

In addition, the parameter making these figures similar is the presence of a limiting shell. At the circle, this is a circle, and the ball has a sphere. Another common feature of them is the fullness of the space between the center of the figure and its limiting shell. This is what distinguishes the described geometric shapes from the circles similar to them, a spherical circle.

The presence of parameters such as radius and diameter is related to these figures. Their value is a fundamental factor when calculating the perimeter, the area of \u200b\u200bthe circle and the volume of the ball.

What is the difference between a circle and a ball?

Considering the question of whether the same figures of the ball and circle, it is necessary to list their differences. The main differences are:

The space of the shape of a figure. A ball is a spatial figure, and a circle can exist only in a plane.
Figures parameters. For the circle, its main parameters will be its area and perimeter. For the ball, the main indicator is its volume, as well as the area of \u200b\u200bthe sphere.
The complexity of reproduction. To portray a circle, it is enough to draw a circle on a sheet of paper using a circul, and then paint over the space between the center and the circle line. To depict a ball on paper, you need to have good skills in drawing geometry, and special equipment will be required to create a ball.

In everyday life, few people ask the question of what the difference between a ball and a circle is. For all objects with similarity to the ball and a circle, it will be more familiar to hear "round". However, knowledge of the differences in these figures and their correct description indicates high literacy and good education.