Diameter of a circle how to#

Public domain images courtesy of wikimedia commons. Now you can figure out the diameter of a circle as long as you know the radius or the circumference or the area. Diameter = 2(square root of the area/pi).The diameter of a circle in this example is 4 meters. If the radius of a circle equals 2 meters, multiply it by 2 to get the diameter.The square root of 4 meters2equals 2 meters. If the area of a circle is 12.56 m2, the radius = the square root of 12.56 meters2/3.14.

Diameter of a circle how to#

HereвЂ™s an example of how to find the diameter of a circle if the circleвЂ™s area is given: Once you know the area, multiply it by 2 to get the diameter.The resulting formula is radius = the square root of the area/pi Solve for the radius by dividing both sides by 3.14 (pi) and taking the square root.Know the formula for the area of a circleвЂ“Area = pi * radius2 (A=в€Џr2). The diameter of a circle is the distance from one edge to the other, passing through the center.If you know the area of a circle, you must manipulate the formula of a circleвЂ™s area by doing the following: If the circumference of a circle is 6.28 inches, the diameter is 6.28 inches / 3.14, which equals 2. If you know the circumference of a circle you can divide it by pi (3.14) to get the diameter (circumference = pi * diameter). If the radius of a circle is 2.47 cm, the diameter is 2.47 cm * 2, which equals 4.94 cm.If you know the radius of the circle, multiply it by 2 to find the diameter. So if you measure the diameter of a circle to be 8.5 cm, you would have: C d. where d is the diameter of the circle, r is its radius, and is pi. Because finding the exact center may prove difficult, itвЂ™s best to take several measurements to ensure accuracy. You can calculate the circumference of any circle if you know either the radius or diameter. If the circle is drawn to scale or if itвЂ™s an actual circle, you can calculate the diameter by measuring from one side of the circle to another, making sure the ruler passes through the circleвЂ™s center. How to find the circleвЂ™s diameter depends on the information available. For our purposes weвЂ™ll stop at the 1/100 slot. Pi/в€Џ - the number pi goes on indefinitely.Center of a Circle - the point inside the circle that is the same exact distance from every point on the circleвЂ™s perimeter.The areaвЂ™s measurement will always be squaredвЂ“in2, ft2, m2, for example. The distance all the way around the circle is called its circumference. Area of a Circle - the total surface of the circle. The diameter is the width of the circle through the center.Circumference - a fancy word for the circleвЂ™s perimeter or boundary.Radius - a straight line from the center of a circle to any point on the circleвЂ™s perimeter.Diameter of a Circle - a straight line that passes through the center of the circle and touches two opposite sides.Before learning how to find the diameter of a circle, itвЂ™s necessary to know the following definitions: Formula to compute the diameter of a circle from the arc height and width D (4H2 + W2) / 4H Calculate the diameter of the circle (or saw blade) Lets use that formula and check that against our calculator result from below: D (4 x 0.125 2) + 2 2 / (4 x 0.125) D (0.0625 + 4) /.