The radius of a circle is a line that starts at the center of the circle and ends somewhere along the perimeter of the circle. The diameter is a line that starts at the perimeter of a circle, goes through the center of the circle, and ends at the opposite perimeter of the circle. This a diameter is twice as long as a radius and can be thought or as consisting of two radii.
The radius is half the diameter (R = D/2). The radius goes from the center of the circle to a point along the perimeter, while the diameter goes across the entire circle, connecting two points opposite each other along the perimeter. If the radius is 7.5 feet, then the diameter is 13 feet.
If you know the radius, double that to get diameter. If you have neither radius or diameter, then measure around the outside.
Pi ( 3.142 approx.) is the amount of times the diameter of a circle can be measured along the circumference of a circle. We know that Pi multiplied by the diameter of the circle is equal to it circumference. So we write C=PiD This means, as it says above, that a certain number of "Pi's" will be equal to the circumference.
-- 12 inches across the circle, along any route that passes through the center -- 6 inches along any radius -- 12 pi = 37.7 inches (rounded) around the circle's curvy line
If you had a circle and cut along the diametre you would get two half cirlces.
The radius of a circle is a line that starts at the center of the circle and ends somewhere along the perimeter of the circle. The diameter is a line that starts at the perimeter of a circle, goes through the center of the circle, and ends at the opposite perimeter of the circle. This a diameter is twice as long as a radius and can be thought or as consisting of two radii.
The radius is half the diameter (R = D/2). The radius goes from the center of the circle to a point along the perimeter, while the diameter goes across the entire circle, connecting two points opposite each other along the perimeter. If the radius is 7.5 feet, then the diameter is 13 feet.
Diameter and width are directly proportional in a circle. As the diameter of a circle increases, so does the width because width is measured along a line passing through the center of the circle. The relationship between the diameter and width remains constant for circles, with width always being half of the diameter.
A good strategy is to use whatever you do know about the circle, along with anyformula that relates the information you do have to the circumference of a circle.
If you know the radius, double that to get diameter. If you have neither radius or diameter, then measure around the outside.
Pi ( 3.142 approx.) is the amount of times the diameter of a circle can be measured along the circumference of a circle. We know that Pi multiplied by the diameter of the circle is equal to it circumference. So we write C=PiD This means, as it says above, that a certain number of "Pi's" will be equal to the circumference.
Pi ( 3.142 approx.) is the amount of times the diameter of a circle can be measured along the circumference of a circle. We know that Pi multiplied by the diameter of the circle is equal to it circumference. So we write C=PiD This means, as it says above, that a certain number of "Pi's" will be equal to the circumference.
-- 12 inches across the circle, along any route that passes through the center -- 6 inches along any radius -- 12 pi = 37.7 inches (rounded) around the circle's curvy line
A semicircle is an example of a figure with one straight line. It is a circle that has been split along the diameter.
That's called a "great circle" of the sphere. -- It's any circle whose center is at the center of the sphere. -- Its diameter is equal to the diameter of the sphere. -- Its area is equal to 1/4 the surface area of the sphere. -- The shortest distance between any two points on the sphere is along the piece of the great circle on which they lie. (There's only one, unless the two points are the opposite ends of a diameter.)
The radian system describes angles in terms of the diameter of a unit circle, i.e. where the radius is 1. If two lines intersect at the radius of a unit circle, the angle in radians between those two lines is the length of the arc along the diameter of the circle delimited by those two lines. The diameter of a unit circle is 2 pi. In the degree system, the angle of one quarter of the circle is 90, while the radians of that same angle is pi / 2. One radian is approximately 57.3 degrees.