You're on a beach on a perfectly still day in a hovercraft. You hover a foot off the ground and drop a plumb bob to the sand. Does it draw a line?

 

yes.

 

i have no answer. and i had to look up what a plumb bob was.

 

Dropping it straight down, and assuming "thought experiment vacuum conditions (sans wind, hovercraft hovers perfectly, etc.)" it should, in theory, be a line. However, once it hits the sand, the point it initially hits the sand (point A) and where it it is drawn up and/or re-dropped (point B) will not be a line.

 

It depends how you look at it. It DOES draw a line in the sense that its continuous, but it will follow the curvature of the earth, so to YOU it might not be perfectly straight, or, if it "hovers" WITH the earth, then no, it will be a dot.

 

Well I think that's the point of the question :-)

I say a hover craft hovers in motion with the earth as there is not enough speed in the rotation of Earth to overcome the small amount of friction that exists between the craft's skirt and the ground it touches.

Would a 1000 foot long piece of string hanging perfectly straight on a perfect still day hang directly straight to Earth, on an angle due to the rotation of Earth?

 

Your balls hang down that low? That's quite a drop to plumb bob.

 

 

Im not exactly sure what you're trying to ask here. Are you asking if the rotation of the earth would cause the plumb bob to draw a line?

 

100% no. The earth spins at 1,000mph at the equator.

1000mph = 16.6 miles per minute = .27 miles per second

If you jumped in the air for 1 second do you come down 1/4 mile from where you started? No.