OldTools Archive

Recent Bios FAQ

270980 Erik Levin 2020‑05‑23 Re: odd question: Gravity well (read for oldtool content - its really there)
James asked about the coin funnel:

I believe you want to look at: https://www.spiralwishingwells.com/guide
/physics.html">https://www.spiralwishingwells.com/guide/physics.html


Near the bottom is the equation (it is a surface of revolution) and near the top
of a dimensioned sketch of an actual device.


I get the impression that it isn't that critical in practice, and the friction
between the coin and the surface have a stabilizing effect, in the same way that
the friction between the tire and the road helps stabilize a bicycle (the
geometry makes it possible, but the friction makes it happen)


*** This message was sent from a convenience email service, and the reply
address(es) may not match the originating address

Recent Bios FAQ