Tuesday, May 5, 2015

Gravity

You may have been wondering, which exerts a greater gravitational pull on you: the sun or spiders? Or you may not have been wondering, but just sort of came upon the question while reading the what-if? blog at xkcd.

Obviously the greatest gravitational pull on each of us is the earth itself, since it is the nearest large object to us. But what about after that? The writer does some math and shows that the sun, being a relatively immense body, makes up for the sheer number of spiders that may be surmised to exist in the world, and even for the fact that the spiders are nearer to us than is the sun.

On the other hand, I can guarantee that seeing a spider in the house -- especially since the area in which I live is prone to fiddlebacks -- creates a pull of my foot towards it with a force that simulates gravity quite nicely. And the end result for the spider is not completely different than the end result of experiencing immense crushing gravity might be for us. Except that in the case of the little Shelob-wannabe, it's richly deserved.

No comments: