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- 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
- 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
- Nuclear fission in the Sun - Physics Stack Exchange
It is estimated that a very small fraction of mass of the Sun (~ $10^{-12}$ times the abundance of hydrogen) is uranium (both 235 and 238 isotopes) But given the huge mass of the sun (~ $2*10^{30}$ kg), the mass of uranium in sun will come to around $2*10^{18}$ kg, which is again a significant quantity
- 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
- astronomy - How big a coincidence is the Sun and Moon having almost . . .
Note that every moon with diameter i will block the sun in 201-i different orbits The smallest moon will block the sun in only one orbit, LEO The probability of a moon 2000 miles in diameter is thus $\frac{1}{200^2}$ that of the smallest moon Then the probability that a moon will block the sun is:
- optics - If the sea surface were absolutely calm should the Sun . . .
As the elevation of the Sun decreases and it moves from the zenith to the horizon, the glitter becomes more and more elliptical, until it becomes a ribbon as in your image On the other hand, if the water were completely still, with a smooth and horizontal surface, then the sun glitter ribbon would be gone, and you would just see a direct
- newtonian mechanics - How come the Suns gravity can hold distant . . .
The Sun is keeping you close After all, you are orbiting it just like the Earth You don't fly off into space because the Earth and you experience the same acceleration due to the Sun's gravitational force, so you orbit together; this is sometimes called the equivalence principle
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