New way to derive sectors of a circle (easy)

In summary, the area of a circle is not 360°, but rather the measure of the angle of a sector. To find the area of a sector in degrees, you can use the formula A=πr^2(φ/360). This can be simplified by converting degrees to radians using the conversion π/180, resulting in A=πr^2(θ/2π).
  • #1
shadowboy13
20
0
So for starters the area of an entire circle has 360º,right?

So we can say that: ##1∏r^2## is ##\equiv## to ##360º##

So by that logic ##0.5∏r^2## is ##\equiv## to ##180º##

And finally ##0.25∏r^2## is ##\equiv## to ##90º##

Divide both sides by 9, and you get : ##0.25∏r^2/9## is ##\equiv## to ##10º##

From that it's much simpler to multiply both sides by some variable.

Simple right?
 
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  • #2
How is that any different to the formula on Wikipedia?
 
  • #3
shadowboy13 said:
So for starters the area of an entire circle has 360º,right?
For starters, the area of a circle is not 360°. That's the measure of the angle of a sector.
shadowboy13 said:
So we can say that: ##1∏r^2## is ##\equiv## to ##360º##

So by that logic ##0.5∏r^2## is ##\equiv## to ##180º##

And finally ##0.25∏r^2## is ##\equiv## to ##90º##

Divide both sides by 9, and you get : ##0.25∏r^2/9## is ##\equiv## to ##10º##

From that it's much simpler to multiply both sides by some variable.

Simple right?
 
  • #4
Try using \pi in your latex code to produce ##\pi## instead of using the product symbol.

If you want to find the area of a sector of a circle that has angle ##\theta## then multiply the area of a circle by ##\theta/2\pi## so

[tex]A=\pi r^2\frac{\theta}{2\pi}=\frac{r^2\theta}{2}[/tex]

However, this assumes that the angle is in radians, but if you want to use degrees instead then just use the conversion

[tex]\text{angle in radians}=\text{angle in degrees}\times \frac{\pi}{180^o}[/tex]

So the formula is then

[tex]A=\pi r^2\cdot\frac{\phi}{360}[/tex]

Where ##\phi## is in degrees. So if ##\phi=360## which would be the entire circle, then as expected, you get ##A=\pi r^2##
 
  • #5


I appreciate your effort to find a simpler way to derive sectors of a circle. Your approach is certainly creative and could potentially be useful in certain situations. However, I would like to point out that your method assumes that the area of a circle is directly proportional to its angle measure, which is not always the case. In fact, the area of a circle is proportional to the square of its radius, not its angle measure. This means that your equation ##1∏r^2## is not equivalent to ##360º##, but rather to ##2∏##. Similarly, ##0.5∏r^2## is not equivalent to ##180º##, but rather to ##∏##. Therefore, your final equation ##0.25∏r^2/9## is not equivalent to ##10º##, but rather to ##∏/9##. While your approach may work for simple cases where the angle measure and area are directly proportional, it may not hold true for more complex cases. It is important to always consider the underlying principles and assumptions behind any mathematical relationship. Keep exploring and questioning, as that is the essence of science.
 

1. How does this new method work?

This new method uses a simple geometric approach to divide a circle into sectors. By drawing a set of radii from the center of the circle to the circumference, the circle is divided into equal angles. These angles can then be used to create sectors of any desired size.

2. Is this method more accurate than traditional methods?

Yes, this method is more accurate than traditional methods because it relies on the fundamental properties of circles and angles. It does not require any complex calculations or estimations, making it a more precise way to divide a circle into sectors.

3. Can this method be used for circles of any size?

Yes, this method can be used for circles of any size. It is not limited by the size of the circle, as long as the circle is perfect and the radii can be accurately drawn from the center to the circumference.

4. Are there any limitations to this method?

There are a few limitations to this method. It can only divide a circle into sectors of equal size, so if you need sectors of different sizes, this method may not be suitable. Additionally, it may not work for circles with irregular or uneven edges.

5. How can this method be applied in real-world situations?

This method can be applied in various real-world situations, such as creating pie charts, dividing a circular field into sections for farming, or dividing a pizza into equal slices. It can also be used in geometry and trigonometry applications to solve problems involving circles and angles.

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