安裝中文字典英文字典辭典工具!
安裝中文字典英文字典辭典工具!
|
- How much lux does the Sun emit? - Physics Stack Exchange
When you look 'at the world' (i e to the horizon) on a clear day, unlesss the sun is at a very low angle, the surface of your eye is not illuminated directly by the sun, only reflected sunlight from the atmosphere, ground and objects The 32,000-100,000 lux figure is referring to a horizontal surface illuminated directly by the sun
- What is the simplest way to prove that Earth orbits the Sun?
If we assume the Sun orbits the Earth, the math says that the Sun should be much less massive than the Earth If we assume the Earth orbits the Sun, the opposite is true Either way we can get an estimate of the mass of the Sun We know from other tests that the Sun is more massive than the Earth, so therefore the Earth orbits the Sun
- How is distance between sun and earth calculated?
Another way of calculating the earth - sun distance is to look at the centrifugal and the gravitational force This solution assumes that one already knows the mass of the sun, but thats a different problem ;-)
- What would happen if Jupiter collided with the Sun?
However, the Sun will accrete $\sim 10^{42}\ \mathrm{kg\ m^2\ s^{-1}}$ of angular momentum, which is comparable to its current angular momentum The accretion of Jupiter in this way is therefore sufficient to increase the angular momentum of the Sun by a significant amount In the long term this will have a drastic effect on the magnetic
- Why is the Sun almost perfectly spherical? - Physics Stack Exchange
The Sun has had plenty of time to reach an equilibrium between its self gravity and its internal pressure gradient, the dynamical timescale for the Sun as a whole is only $\sim (GM_\odot R_{\odot}^3)^{-1 2} \simeq 1600$ s Any departure from symmetry would imply a difference in pressure in regions at a similar radius but different polar or
- How much iron would I have to shoot into the Sun to blow it up?
The sun's temperature at the surface is ~5778 Kelvin which is much higher than the boiling point of Fe, Ni, or any alloy of the Fe-Ni The atoms would disperse and would become lost in the sea of H and He nuclei, and wouldn't conceivably come anywhere near the core in one piece Literally nothing about the sun would change in this scenario
- Why doesnt sun go all the way to the horizon during sunset?
However, there may be an illusion where sun's position at horizon may appear slightly different than it actually is due to atmospheric refraction It may be useful to read this Also, in the second image, there appars to be layer of clouds under the sun, maybe the sun is disappearing behind those while still remaining above horizon, i e not
- Where will the Goldilocks zone be when the Sun becomes a red giant?
Distant future of the Sun and Earth revisited Monthly Notices of the Royal Astronomical Society, 386(1), 155-163 As the sun evolves it will first become a sub-giant The sun is estimated to reach its hottest surface temperature of 5820 K in 2 55 Gyr with a luminosity 1 26 times brighter than at present
|
|
|