Sphere call a set of all points in the space stretching from a point center at distance of a certain radius of R. Radius in turn is the piece connecting the center of a sphere to any point of its surface.
It is required to you
- - formula of a surface of the square of a sphere;
- - sphere volume formula;
- - skills of the arithmetic account.
Instruction
1. In everyday life often there is a need to calculate the area of a spherical surface or its part to calculate, for example, a material consumption. Having calculated sphere volume, you can calculate the mass of the substance making sphere contents through specific weight. To find the area and volume of a sphere, it is enough to know its radius or diameter. On formulas which today's school students remove in the 11th class of comprehensive school you can easily calculate these parameters.
2. For example, diameter of a soccerball, according to all requirements of FIFA, has to be within 21.8 — 22.2 cm. Average up to 22 cm for simplicity of the account. Therefore, radius (R) will be equal (22:2) – 11 cm. It is interesting to learn what surface area of a soccerball?
3. Take a sphere surface area formula: Sshara = 4ttR2Podstavte in the given formula value of radius of a soccerball – 11 cm of S = 4 x 3.14 x 11х11.
4. After carrying out simple mathematical operations you receive result: 1519.76. Thus, the surface area of a soccerball is 1,519.76 square centimeters.
5. Now calculate ball volume. Take a formula of calculation of volume of a sphere: V = 4/3ttR3Podstavlyayte besides value of radius of a soccerball – 11 cm of V = 4/3 x 3.14 x 11 x 11 x 11.
6. After calculations, for example, on the calculator you receive: 5576.89. It appears, air volume in a soccerball is 5,576.89 cubic centimeters.