Calculate the volume of a cylinder with a length of 20cm, and whose circular end has a radius of 2.5cm. First, work out the area of one of the circular ends of the cylinder. The area of a circle is ?r2 (? × radius × radius). ? (pi) is approximately 3.14. read more
Volume of a Sphere. As with a circle, you need π (pi) to calculate the volume of a sphere. The formula is 4/3 × π × radius 3. You may be wondering how you could work out the radius of a ball. Short of sticking a knitting needle through it (effective, but terminal for the ball!), there is a simpler way. read more
The circle's diameter, in turn equals twice the radius. A regular solid that has a circle as a face is called a cylinder. Like all geometric prisms, a cylinder's volume is the product of its cross-sectional area and its length. The cross-sectional area is the area of its circle, and you can calculate it from the circle's radius. read more