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1

The above isn't drawn correctly. And it is far too complicated in my opinion. I think I was able to solve this using high school physics: This bugged me a long time. I am surprised no one ever posted an answer on the internet. The length of his rope was 60.8 meters, assuming a drop above the target building of about 12 meters. The difference in height ...

0

Earth's gravitational field causes Earth to retain a gaseous atmosphere, which both absorbs light itself and refracts light towards the surface. Estimating the altitude of the optically thick part of the atmosphere as somewhere between 6 km and 60 km, this atmosphere effectively increases the cross-sectional area of the Earth for interacting with sunlight ...

3

(This should have been a comment but got too long for the comment box.) That's not the only environmental cost associated with the change. Consider a daytime accident caused by one driver who failed to see another, which could have been averted if both drivers had been using their headlights. Now you have two vehicles which require replacement body panels,...

2

If you add mass to the Earth, or the "Earth system", it makes not the slightest bit of difference to the orbit unless you also change the Earth's angular momentum around the Sun. That is because the basic dynamical equation controlling the orbit is that the inward gravitational force due to the the Sun is equal to the mass times centripetal acceleration. ...

3

The effect is noticeable even here on Earth, and in fact it has been used to measure the mean density of the Earth in experiments such as the Schiehallion experiment. The principle is simple: take a pendulum. If there is no large-mass object nearby (such as a mountain), it will hang straight downward, pointing to the center of the planet. But if there is a ...

11

The power radiated by a charged particle moving at non relativistic speeds, whose acceleration is $a$ and charge is $q$, is given by the Larmor Formula $$P =\frac{2q^2a^2K}{3c^3}.$$ The product above is nowhere near $c^3$ for planetary motion and hence the radiation emitted is negligibly small.

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