In geometry lessons at school, we all studied the properties of various shapes and lines. Each of them has its own characteristics, and sometimes some of them are interconnected with each other. Take, for example, at least a circle and a circle - there is a certain connecting line between them. Just what is it? Let's look into this issue together.
Circle is an infinite number of points that are at the same distance from one single point, called the center of the circle. Connected points form a curved line, which will be a circle. All points that are at a different distance from the center of the circle will not be on this line, so they will not be included in the circle. Accordingly, a circle is a geometric figure that represents a certain line, and everything that is inside or outside it does not apply to a circle. For this reason, there is a clear concept that the circle divides the entire plane into two parts - the inner, limited by the line of the circle, and the outer, unlimited, since the plane in the general sense has no boundaries.
A circle is a geometric figure, the boundary of which consists of an infinite number of points equidistant from the center of the circle. All internal space, as well as the center of the circle, belong to it, so we can say that the circle is a certain area of space, limited by many points. And since these points are equidistant from the center, the circle will be the boundary of the circle. The entire outer space does not belong to the circle, but it covers the entire part of the plane that is outlined with the help of a circle.
The differences between a circle and a circle are not so great, since these figures represent an incalculable number of points in the plane that are at the same distance from one central point. But an important distinguishing feature is the fact that the inner space does not belong to the circle, but is necessarily an integral part of the circle. In other words, a circle is not only a circle, which is its boundary, but also an infinite number of points that are inside this circle.
ImGist determined that the difference between a circle and a circle is as follows:
The circumference is only a part of the circle, its boundary, while the circle is a more extensive and complete figure;
A circle is a curved line consisting of an infinite number of points equidistant from the center, and a circle is not only the sum of these points of the circle, but also all those points that are located inside this very circle.
Circle- this is a huge number of points on the plane, equidistant from a certain point of the same plane, called the center of the circle. A circle is a closed curve lying at a fixed distance from the center, which is cut by the radius of the circle.
A circle- this is a huge number of points of the plane, remote from a certain point of the same plane, called the center of the circle, at a distance not exceeding a certain value, called the radius of the circle. A circle is a solid figure that includes a circle and all the points that lie in it.
Therefore, a circle is a section of a plane, and a circle is a feature of this section. Therefore, it is possible to speak of the area of a circle and the circumference of a circle, but it is wrong to speak of the length of a circle and the area of a circle.
Since the points of the circle are removed from the center by a distance not exceeding the radius, they all belong to the circle. In other words, the circle belongs to the circle it encloses. In special cases, a circle can be considered in the absence of a boundary - a huge number of points of a circle that do not belong to its boundary (circle).
The circle divides the plane into two parts - lying inside and lying outside. Crawling from one part to another is unrealistic in the absence of a crossing of the circle. The area of the inner part is finite, the area of the outer part is infinite.
The center of the circle does not belong to the circle (except for the degenerate variant of the circle of zero radius). The center of a circle always belongs to the circle, because is inside the bounding circle.
NMitra There is a bug in Opera: corners of a nested element are not rounded. This can be corrected by adding
#ball:after(
content: "";
position: absolute;
top: 0; bottom: 0; right: 0; left: 0;
box-shadow: 0 0 0 100px #fff;
border-radius: 100%
}
But then the shadow in Google Chrome "cropped" is obtained. Since Opera is moving to the Google engine, I made a choice in favor of its browser. Cosmo Mizrael Cool.
Right now I'm doing a design with planets, but avatars and other images have to be made flat, because img can't apply box-shadow: inset. NMitra Set the background to background. Soon, thanks to CSS transform support, it will be possible to add volume. Forerunners http://codepen.io/html5web/pen/pnbwo Cosmo Mizrael Mdo, it seems to be for a webkit, but it doesn’t work
It’s not always possible to make backgrounds, but it’s very possible to overlay an element with specified styles on top of the image. But this is if the dimensions of the image are known.
Example: http://jsfiddle.net/9qzm6/
I also found a script that does this job on its own:
http://www.htmldrive.net/items/demo/1156/Multiple-CSS3-Image-Styles
Here he himself determines the size if the image has loaded. You need jQuery.
This is so, note 🙂 NMitra Some settings need to be set there .. This is a lot forward :))
Please 🙂 I've been a regular reader for at least a year 🙂 Anonymous IE 11
Everything is animated)) NMitra Well done IE, reached out. It remains for Chrome to remove -webkit-, he is now among the lagging behind.
What is a circle?
The outline of a circle starts with a circle. Circumference - it is a closed line without end and beginning, each point of which is at the same distance from the center. The simplest example of a circle is a gymnastic hoop.
A circle will turn out if you draw a circle, for example, on paper - and then decorate it. Any colors: yellow, blue, green - whichever you like best. The main thing is to fill the void with something. After the end of the work, the circle will turn into a figure, which is called a circle. A circle, in essence, is some part of a two-dimensional surface, looped into a circle.
The circle has some important parameters for understanding its essence. By the way, some of these parameters are also inherent in the circle.
- Radius- the distance from the center point of the circle or circle to the border of the figure (the line that outlines it).
- Diameter- an important characteristic that appears so often in school assignments. This is the sum of two radii, that is, the distance between two opposite points on a circle.
- Square- a property characteristic only for a circle. The circle does not have it due to its structure (because it is empty, and the center of the figure is an imaginary point). In a circle, on the contrary, it is not difficult to determine the center. Through the central point of the figure, it is enough to simply draw a series of lines that will divide the circle into sectors.
Circle in real life
In reality, you can easily find many objects that are identical in shape to a circle. For example, a ready-made sample of a circle - or rather, a set - rolls along the roads of towns and cities every day. It is clear that we are talking about the wheel. Here it is worth making a reservation: the circle should not be monophonic, it is not necessary. It can be decorated with patterns or something else - this does not change the shape.
Another example of a circle is The sun. Yes, the same daylight that people see every day. An inquisitive reader will notice that the Sun is a three-dimensional figure; it cannot be a circle. It's true. But the small figure, which the fiery star appears to the inhabitants of the Earth, is essentially a circle. Its area, of course, cannot be calculated. Why? Because this example is given only for clarity, in order to understand what a circle is.
Sector
The attentive reader has already figured out what a circle is. But what kind of "beast" is this sector, which was mentioned a little higher? A sector is a part of a circle separated from the rest of the surface by a pair of drawn radii. For clarity, we can take this example: everyone has ever seen a sliced pizza. Pieces are sectors of the circle, which is the whole appetizing dish.
The sectors do not have to be equal in size. For example, if a pizza is cut in half, both halves will also be sectors of the circle.
What is a ball?
Ball - body bounded by a spherical surface. That is, it is not a two-dimensional figure, like a circle, but three-dimensional. A spherical surface is a geometric combination of a surface of points located at a non-negative distance from some central point. The distance at which all points on the surface of a sphere are removed from its center is called the radius. And it should not exceed certain given numbers. Thus, a circle is the same spherical surface located in a different space.
This shows the similarities and the main difference between the ball and the circle. A circle is a two-dimensional figure whose points are bounded by a circle. A ball is a three-dimensional figure, and its points are limited by a spherical surface.
Varieties of the ball
In metric and vector spaces, two concepts are considered that have a connection with a spherical surface. The sphere that includes this sphere is called closed. A ball that does not include a sphere is called open.
Ball characteristics
A sphere, like a circle, has a diameter and a radius. Both of these quantities in the ball are calculated according to the principles described above (as for a circle). The radius of a ball is the segment between any point on the spherical surface bounding the figure and its center. The diameter connects two points on the spherical surface of the ball, passing through its center.
An interesting addition: a circle can be part of a ball. More precisely, the ball consists of a very large number of circles of different diameters. These circles are called sections of the sphere. When the section runs through the center of the ball, it is called a great circle. All other sections are called small circles. Such sections passing through a pair of points on the surface of the ball, it is possible to draw a truly infinite set.
findings
A circle is a flat, two-dimensional figure. A ball is a three-dimensional geometric body. However, they have a lot of similarities (the presence of a bounding surface, diameter and radius, the fullness of the structure, in contrast to the same circle, the ability to calculate the area).
What is the difference between a circle and a sphere? The circle is flat, the ball has volume. It is the volume of the ball that allows it to be divided into sections, which are essentially circles. The circle, on the contrary, is divided into sectors.
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Let's understand what a circle and a circle are. Formula for the area of a circle and the circumference of a circle.
Every day we meet a lot of objects that form a circle or, on the contrary, a circle. Sometimes the question arises, what is a circle and how does it differ from a circle. Of course, we all took geometry lessons, but sometimes it doesn’t hurt to refresh our knowledge with very simple explanations.
What is the circumference and area of a circle: definition
So, the circle is a closed curved line that limits or, on the contrary, forms a circle. A prerequisite for a circle is that it has a center and all points are equidistant from it. Simply put, a circle is a gymnastic hoop (or as it is often called a hula hoop) on a flat surface.
The circumference of a circle is the total length of the curve that forms the circle. As you know, regardless of the size of the circle, the ratio of its diameter and length is equal to the number π = 3.141592653589793238462643.
It follows from this that π=L/D, where L is the circumference and D is the diameter of the circle.
If you know the diameter, then the length can be found using a simple formula: L= π* D
If the radius is known: L=2 πR
We figured out what a circle is and can move on to the definition of a circle.
A circle is a geometric figure that is surrounded by a circle. Or, a circle is a figure, the boundary of which consists of a large number of points equidistant from the center of the figure. The entire area that is inside the circle, including its center, is called a circle.
It is worth noting that the circle and the circle that is in it have the same radius and diameter values. And the diameter, in turn, is twice the radius.
A circle has an area in a plane, which can be found using a simple formula:
Where S is the area of the circle and R is the radius of the given circle.
What is the difference between a circle and a circle: an explanation
The main difference between a circle and a circle is that a circle is a geometric figure, while a circle is a closed curve. Also note the differences between a circle and a circle:
- The circle is a closed line, and the circle is the area inside this circle;
- A circle is a curved line on a plane, and a circle is a space closed into a ring by a circle;
- Similarities between circumference and circle: radius and diameter;
- The circle and the circle have a single center;
- If the space inside the circle is shaded, it turns into a circle;
- A circle has a length, but a circle does not, and vice versa, a circle has an area that a circle does not.
Circle and circle: examples, photos
For clarity, we suggest considering a photo in which a circle is shown on the left, and a circle on the right.
The formula for the circumference and area of a circle: a comparison
Circumference formula L=2 πR
Circle area formula S= πR²
Note that in both formulas there is a radius and a number π. It is recommended to learn these formulas by heart, as they are the simplest and will definitely come in handy in everyday life and at work.
Circle area along the circumference: formula
S=π(L/2π)=L²/4π, where S is the area of the circle, L is the circumference.
Video: What is a circle, circle and radius
In geometry lessons at school, we all studied the properties of various shapes and lines. Each of them has its own characteristics, and sometimes some of them are interconnected with each other. Take, for example, at least a circle and a circle - there is a certain connecting line between them. Just what is it? Let's look into this issue together.
Circle is an infinite number of points that are at the same distance from one single point, called the center of the circle. Connected points form a curved line, which will be a circle. All points that are at a different distance from the center of the circle will not be on this line, so they will not be included in the circle. Accordingly, a circle is a geometric figure that represents a certain line, and everything that is inside or outside it does not apply to a circle. For this reason, there is a clear concept that the circle divides the entire plane into two parts - the inner, limited by the line of the circle, and the outer, unlimited, since the plane in the general sense has no boundaries.
A circle is a geometric figure, the boundary of which consists of an infinite number of points equidistant from the center of the circle. All internal space, as well as the center of the circle, belong to it, so we can say that the circle is a certain area of space, limited by many points. And since these points are equidistant from the center, the circle will be the boundary of the circle. The entire outer space does not belong to the circle, but it covers the entire part of the plane that is outlined with the help of a circle.
The differences between a circle and a circle are not so great, since these figures represent an incalculable number of points in the plane that are at the same distance from one central point. But an important distinguishing feature is the fact that the inner space does not belong to the circle, but is necessarily an integral part of the circle. In other words, a circle is not only a circle, which is its boundary, but also an infinite number of points that are inside this circle.
Findings site
- The circumference is only a part of the circle, its boundary, while the circle is a more extensive and complete figure;
- A circle is a curved line consisting of an infinite number of points equidistant from the center, and a circle is not only the sum of these points of the circle, but also all those points that are located inside this very circle.
