Tuesday, May 27, 2008

Star What?

The main characteristics of a series of stars that can be understood in different physical processes inside. First, the hydrostatic balance, also called hydrostatic equilibrium. This structure determines the density of the star that the pressure gradient internal balances against gravity. Another way to think about what it is conceivable that the star of a large number of fine particles spherical nested cups (so to speak like an onion). The forces operating in each environment of the gravitational pull of all the cups to him, and gas and pressure of radiation on the outer face of the cup. The only force outside of each Shell is the gas and radiation pressure inside the cover, there is no force of gravity equipment outside the shell (this is known as Gauss theorem). The balance hydrostatic forces, active and passive must be balanced. If they do not, is the interpreter of collapse or expand. The timing of these come, as "free fall schedule," and it is 2000 seconds for a star like the sun. As we know, the sun was more or less stable over the age of the Earth (several billion years), the hydrostatic balance must be maintained for a very high precision. One consequence of the hydrostatic balance is that the pressure on Shell any material from outside, it must be less than the pressure inside equipment. This is because gravity acts only in the direction active. Thus, the pressure on the star must be increasingly radius of decline. This is a consequence intuitively obvious, the pressure in the center of the star is greatest when it comes to the surface.