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$G$ was historically calculated from the Cavendish experiment, involving balls and a torsion balance. The earth's mass was actually calculated before the sun's mass. Using the assumption that the earth was a sphere, its circumference and thus its radius could be determined through geodesy, as was done historically even before Newton. The acceleration of an ...


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When 1686 Newton writes "Principia...", the inertial frame concept does not exist yet. However, we can find in it Corollary IV (introducing the center of mass CM concept for any interacting body set), Corollary V (Galileo's Principle of Relativity, applied to any limited body set with CM at any uniform velocity), and the today almost forgot Corollary VI (a ...


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Even if the original dust cloud only had a relatively small angular velocity (which it might have had for all sorts of reasons), the process of collapsing would have amplified it. That is, the collapse process preserves the angular momentum, but it translates to a much larger rotational speed in the newly-collapsed system. Think of what happens to a spinning ...


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Short Answer So the short answer is turbulent motion of the photospheric plasma on the sun. Long Answer The underlying physical mechanism is related to the concept of frozen-in magnetic flux, which is assumed in ideal MHD. This can be derived in a similar manner to how one derives the conservation of vorticity, but here it is magnetic flux. If we define ...


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The materials that made up the solar system can be studied through the analysis of pre-solar grains and the abundances of various isotopes in primitive meteoritic material. Pre-solar grains were formed in the photospheres of stars pre-dating the Sun. These grains were then expelled into the interstellar medium (ISM) in stellar winds and also in supernova ...


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This is a complicated problem but if we make several assumptions, we can an order of magnitude estimate that should address your question. Power Source First, the sun is the source of power/energy, and we know its luminosity is ~ $3.846 \times 10^{26}$ W. Therefore, the power per unit area at various distances can be determined by dividing this result by ...


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It all depends on the closest approach of any stars to the Sun. When galaxies collide it is not that their stars crash into each other, because their individual cross-sections are extremely small when compared to the space between them. This is dealt with in qualitative terms on the wikipedia page on the likely collision. The Milky Way disk at the ...


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I was wondering that if they were orbiting in same orbit then will they both have same time period? If yes, then why because as they both have different angular momentum and both have so much of differences. I'll break this down into two parts, first looking at the period of individual objects orbiting the Sun at a distance of one astronomical unit (but ...


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The rotation period $T$ is given by $$T=2\pi \sqrt{\dfrac{a^3}{G(M_\text{Sun}+M_\text{planet})}}$$ where $a$ is the sum of the half axes of the ellipse. Routhly: $M_\text{Sun}=2\times 10^{30}$ kg $M_\text{Earth}=6\times 10^{24}$ kg $M_\text{Jupiter}=2\times 10^{27}$ kg If you assume both Earth and Jupiter are orbiting around the Sun (and neglect the ...


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A collapsing gas cloud is an open system. It loses mass, energy and angular momentum as it collapses. Even if the net angular momentum of the cloud is zero, after the collapse the final planetary disk can have a significant net angular momentum, and the ejected material will have the opposite angular momentum. What can not happen, and that's where your ...



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