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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
  • 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
  • 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 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
  • visible light - Is sunlight truly white? - Physics Stack Exchange
    In fact, helium was first discovered by astronomers observing the sun's corona during a solar eclipse The low pressure helium in the corona emitted the helium emission spectrum that was observed unaltered on earth Meanwhile, the high-pressure helium in the body of the sun was emitting the usual continuous spectrum
  • sun - What exactly is delta-14C and why are there periodic plateaus in . . .
    The reason the Delta 13C has waves is because the amount of carbon 14 in the air depends on the amount of cosmic rays before that time, but the amount of cosmic rays goes up and down (mostly due to sun activity) Another isotope that depends on cosmic ray abundance in the atmosphere is beryllium-10 Carbon 14 has a half life of about 6000 years
  • How hot can metal get in sunlight? - Physics Stack Exchange
    If the building is located in Hammerfest, Norway the metal might get warm to the touch If it's on the sun-facing side in Las Vegas you may find it gets hot enough to cause burns A definitive answer is not possible If people can touch it easily the temperature is a concern If it's out of reach, don't worry about it The iron isn't going to melt
  • What is actually meant by sun set and sun rise times, when taking . . .
    The Sun has actually set risen and we see it due to the way light is bent across the atmosphere Apparently due to coincidence of the size and distance of the sun, its exactly the same size - so if we see 50% of the sun, the sun is 50% below the horizon So, I understand all this, so here is my question :


















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