Circle has infinite sides how many sides does a semi circle have?

In summary, the conversation discusses the concept of a circle having infinitely many "sides" and how this relates to finding the number of "sides" in a semicircle. It is suggested to continue dividing regular polygons in half to determine the number of "sides." However, this definition of a circle as having sides is considered questionable. It is also mentioned that any curve can be seen as having an infinite number of "sides."
  • #1
Noj Werdna
13
0
If a circle has infinite sides how many sides does a semi circle have?
i have asked my teachers at school but they have ll said u wud have 2 divide infinity by 2 and +1 which obviously isn't possible cos infinity isn't reli a number is it...

Thanks
 
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  • #2


A circle is said to have infinitely many "sides" due to the analogy with regular polygons.
(i.e. a triangle has 3, a square 4, and so on)
Eventually you get a shape with so many sides that it "becomes" a circle.
If you want to find how many "sides" a semicircle has, just continue in the same way...
Cut regular polygons in half and work out how many sides they have
(i.e. half a triangle has 3 sides half a square has 4, half a pentagon... etc)

Do you see the idea?

(It's just a bad/weird definition of a circle, since it doesn't really have sides, does it?)
 
  • #3


Any curve can be looked at as having an infinite number of 'sides' whose length goes to zero, no matter how big.
 
  • #4


there are two sides to a circle - inside and outside. (posted lest someone begin to take this more seriously than the topic deserves)
 

1. How can a circle have infinite sides?

A circle is a geometric shape that is perfectly round, with no edges or corners. It is defined as the set of all points in a plane that are equidistant from a given point, known as the center. This means that no matter how small we make the sides of a circle, we can always divide it into smaller parts, making it have an infinite number of sides.

2. Does a semi-circle have half the number of sides as a circle?

No, a semi-circle is a half of a circle and therefore has the same number of sides as a full circle - infinite. The number of sides does not change, regardless of how much of the circle is visible.

3. Is a semi-circle considered a polygon?

No, a semi-circle is not considered a polygon. A polygon is a 2-dimensional shape with straight sides connecting at angles, while a semi-circle is a curved shape with a circular boundary. Therefore, it does not fit the definition of a polygon.

4. Can a semi-circle be divided into smaller parts like a circle?

Yes, a semi-circle can be divided into smaller parts just like a circle. The difference is that a semi-circle can only be divided into 180 degrees, while a circle can be divided into any number of degrees. This is because a semi-circle is only half of a circle.

5. How many sides does a semi-circle have in terms of radians?

In terms of radians, a semi-circle has a total of π (pi) radians. This is because a full circle has 2π radians, and a semi-circle is half of a circle. Therefore, a semi-circle has half of the number of radians as a full circle.

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