“Give me a place to stand, and I will move the Earth.” So, famously, said Archimedes, dramatizing his newly discovered law of the lever. Which in this case takes the form

*Force exerted by Archimedes *x *distance from Archimedes to fulcrum *equals

*Mass of Earth *x *distance from Earth to fulcrum.*

Now, I don’t think Archimedes was interested in the position of the Earth in space, but he did want the fulcrum to be fixed. (I know he *said ‘*a place to stand’, but if the fulcrum moves, all bets are off, so presumably that’s what he meant.) He also needed a perfectly rigid lever of zero mass, and he probably did not realize that he also needed uniform gravity, contrary to astronomical fact, to convert mass to weight. No matter, I don’t want to get into discussions about inertia or other quibbles. Let’s grant him all those things. My question is: when the Earth moves, how *far* does it move? And, can Archimedes achieve the same result more easily?

(Ref: Prof Ian Stewart’s Cabinet of Mathematical Curiosities).

More later,

Nalin Pithwa