To calculate the area of a side surface of a cylinder happens it is necessary in various situations. For example, you want to sew a cover on a pillow roller and you need to define a fabric consumption. Or you are going to paint a round barrel and have to calculate amount of paint. And can be you are faced by a task to paste over with wall wall-paper in the round room? In all these cases you will face a task on determination of the area of a side surface of a cylinder.
It is required to you
- Calculator, roulette or centimetric tape
Instruction
1. The side surface of a cylinder in expanded form represents a rectangle. The formula for calculation of the area of a side surface of a cylinder is simple: Sbok = LhHgde Sbok is the required area of a side surface of a cylinder. The right part of equality is presented by the work of two multipliers: L — length of a circle of the measured cylinder, N — its height. In turn circle length in the basis of a cylinder is calculated on a formula: Pi's L= x Pi's Dgde — Pi's number, size constant and equal 3.1416 D — diameter of a circle in the cylinder basis. The practical way of determination of the area of a side surface of a cylinder is chosen on circumstances.
2. Write down everything the data on a cylinder which are available for you which area of a side surface you need to determine. If height and diameter of a cylinder are known, then just substitute these parameters in a formula. Knowing height and diameter of an advertizing curbstone, it is possible to calculate the poster size. At the same time it is absolutely optional to see and measure a cylindrical curbstone on which the poster will be placed.
3. Take a centimetric tape or a roulette for determination of length of a circle in the cylinder basis if the sizes of a cylinder are unknown. In the absence of the flexible measuring tool it is possible to manage any rope, a cord or a tape. Determine length of a circle of the basis of a cylinder by a rope. Measure the received piece of a rope by any measuring tool, for example a tailor's ruler.
4. Determine cylinder height. At measurement of height of a cylinder it is important to adhere strictly to a vertical for obtaining exact result. Definition of the line of a vertical also requires a rope on which ends any cargo is attached. For example, usual nuts. Fix one end of a rope on the basis of a cylinder. The rope under weight of cargo will reach strictly vertical position. Along the line of a vertical it is also necessary to carry out measurement of height of a cylinder. Multiply two parameters received at measurements. The result of multiplication is also the area of a side surface of a cylinder.