Skip to main content
36 votes

Why is pressure in the outermost layer of a star lower than at its center?

Considering the only force keeping the star together is gravitational in nature, Gravity is also what's keeping our oceans stuck to the Earth's surface. Where's the pressure at its highest, near sea ...
Flater's user avatar
  • 890
17 votes
Accepted

Why is pressure in the outermost layer of a star lower than at its center?

There is a lot of mass above the centre, pushing down on it. On the surface there is no mass above. Hence you get high pressure at the centre and zero at the surface.
Anders Sandberg's user avatar
7 votes

Why is pressure in the outermost layer of a star lower than at its center?

This is an exercise in hydrostatics. Imagine the sun consisting of a sphere of water. The deeper you go beneath the surface, the more water weight you have bearing down on you from above, and the ...
niels nielsen's user avatar
7 votes
Accepted

Is the size of a black hole singularity smaller than a fundamental particle?

The very short answer to this is: We have no idea. General relativity predicts that the singularity of a Schwarzschild black hole (which I assume is what you mean by "actual black hole") is ...
paulina's user avatar
  • 1,897
6 votes

Is the size of a black hole singularity smaller than a fundamental particle?

While @paulina's answer: we don't know is correct, because quantum gravity is not understood, I'll answer for a classical Schwarzschild blackhole as described by Kip Thorne. The size is zero, however ...
JEB's user avatar
  • 35.4k
6 votes

Why is pressure in the outermost layer of a star lower than at its center?

Perhaps the confusion in the question arises because you are thinking of a rigid spherical shell of constant density, and you know that inside such a shell the gravitational field is zero? A ball of ...
C.M.O.B.'s user avatar
  • 109
5 votes

Is the size of a black hole singularity smaller than a fundamental particle?

We know that black hole is infinitely densed. More exactly: The theory of general relativity predicts that the center of a black hole is infinitely dense. This theory predicts very well everything ...
Thomas Fritsch's user avatar
4 votes

Why is pressure in the outermost layer of a star lower than at its center?

I believe you are confusing "force of gravity" with "pressure." The gravitational pull (or local acceleration $g$) is indeed zero at the center of the Sun, and a maximum elsewhere ...
RC_23's user avatar
  • 9,500
2 votes
Accepted

Why Cepheids have Period Luminosity relation?

The timescale of any large scale radial variation in a star will, even on a dimensional basis, be proportional to $(G\bar{\rho})^{-1/2}$, where $\bar{\rho}$ is the average density. Thus $$T \propto M^{...
ProfRob's user avatar
  • 133k

Only top scored, non community-wiki answers of a minimum length are eligible