How To Draw A Circle With A Circumference Of Pi Squared
Circumvolve
 | A circle is easy to make: Describe a bend that is "radius" away And so: All points are the same distance from the center. |
You Can Draw It Yourself
Put a pin in a board, put a loop of string effectually information technology, and insert a pencil into the loop. Keep the string stretched and draw the circle!
Play With It
Endeavour dragging the point to run across how the radius and circumference modify.
(See if you can continue a abiding radius!)
Radius, Diameter and Circumference
The Radius is the altitude from the eye outwards.
The Diameter goes straight across the circle, through the middle.
The Circumference is the altitude once effectually the circle.
And here is the actually cool thing:
When we divide the circumference by the diameter we get 3.141592654...
which is the number π (Pi)
| Then when the bore is ane, the circumference is iii.141592654... |  |
We can say:
Circumference = π × Bore
Example: You walk around a circle which has a diameter of 100m, how far have you lot walked?
Altitude walked = Circumference = π × 100m
= 314m (to the nearest g)
Also note that the Bore is twice the Radius:
Bore = two × Radius
And and so this is also true:
Circumference = two × π × Radius
In Summary:
| Radius | Diameter | Circumference |
Remembering
The length of the words may assistance you remember:
- Radius is the shortest word and shortest measure
- Diameter is longer
- Circumference is the longest
Definition
 | The circumvolve is a plane shape (two dimensional), so: |
Area
The expanse of a circle is π times the radius squared, which is written:
A = π rii
Where
- A is the Expanse
- r is the radius
To help yous remember remember "Pie Are Squared" (even though pies are normally round):
Case: What is the expanse of a circle with radius of 1.2 g ?
Surface area = πrtwo
= π × one.ii2
= 3.14159... × (1.2 × 1.2)
= 4.52 (to ii decimals)
Or, using the Bore:
A = ( π /4) × D2
Area Compared to a Square
A circle has about 80% of the area of a similar-width square.
The actual value is (π/4) = 0.785398... = 78.5398...%
And something interesting for you:
Run into Circle Area by Lines
Names
Because people have studied circles for thousands of years special names have come up about.
Nobody wants to say "that line that starts at one side of the circle, goes through the heart and ends on the other side" when they can merely say "Diameter".
So here are the most mutual special names:
Lines
A line that "just touches" the circumvolve as it passes past is called a Tangent.
A line that cuts the circle at ii points is chosen a Secant.
A line segment that goes from 1 bespeak to another on the circle's circumference is called a Chord.
If it passes through the middle it is called a Bore.
And a part of the circumference is called an Arc.
Slices
There are ii main "slices" of a circle.
The "pizza" slice is called a Sector.
And the slice made by a chord is called a Segment.
Common Sectors
The Quadrant and Semicircle are 2 special types of Sector:
Quarter of a circle is called a Quadrant.
Half a circle is called a Semicircle.
Inside and Outside
A circle has an inside and an outside (of grade!). But it besides has an "on", considering nosotros could be right on the circumvolve.
Example: "A" is exterior the circle, "B" is inside the circle and "C" is on the circle.
Ellipse
A circumvolve is a "special case" of an ellipse.
Source: https://www.mathsisfun.com/geometry/circle.html
Posted by: levinespinat.blogspot.com
0 Response to "How To Draw A Circle With A Circumference Of Pi Squared"
Post a Comment