For a circle, area = Pi x radius2
Area of Circle = pi (radius)2 So , using this formula we can find the radius and also the diameter. Diameter = 2(radius)
Formula of Circumference of a circle: 3.14*Diameter of the circle. You could also do: 3.14*3.14*radius.
D= 2r where r= radius. Also Circumference/pi = D
Aryabhatta found area of circle as pi*d^2/4 which is equal to pi*r^2. He gave direct results in his book aryabhattiyam. He also stated volume of sphere as 1.776pi*r^3, which is approximately correct.
Surface area (SA) = (2 x pi x radius x h) + (2 x pi x radius squared) also the formula for an open cylinder includes: (2x radius square x height) + (pi x radius square)
To calculate this you will need the diameter of the circle. The formula is: diameter/2*pi If you don't know the diameter you can also use the area of the circle: Sqrt(Area/pi) = radius
you must know the radius also. Then use the formula arc = 2 x 3.14 x radius x angle / 360
You came to the right place.The formula for the volume of any cylinder isVolume = (pi) x (Radius)2 x (Length) .It can also be found in books.
The formula for the circumference of a circle is C = 2πr where r is the radius. This formula can also be expressed as C = πd where d is the diameter as the diameter is twice the radius. C = 15π = 47.12cm (2dp)
1. The radius of a circle is half of its diameter.2. The radius can also be calculated from its circumference (C).Method: Divide the circumference by Pi, this will give you the diameter. Then divide the diameter by 2 to get the radius (r).Formula: r = C/2π3. The radius can also be calculated from the area of the circle. Area = π x r2So, divide area by Pi, then the radius will be the square root of the answer.For more information, try the Related links below.
The diameter would be 8cm, because the diameter is always double the radius. That's why the formula 2'Pi'r is also known as 'Pi'd.
the formula for the area of a circle is A = pi * r^2 also, diameter = 2 * radius therefore, the radius must equal 2.1 therefore, A = 4.41*pi you can leave it in that form, but if you wanna evaluate and find a numerical value by using 3.14 instead of pi, you will get 13.8474