William Beaty wrote: > On Fri, 3 Jul 2009, Stephen A. Lawrence wrote: > > >> No, the force should have been the same in each trial. Think about what >> you've got. >> >> If each layer is behaving elastically, then the question you need to ask >> is, what force is needed to compress 1 layer to 1/2 its thickness? Call >> that force "F". >> > > Nah, the stuff is really rigid, and the stack visibly remains flat when > squeezed. (That's probably a good clue that there were no air layers in > the first place!) It's probably the plastic case connected to the > micrometer jaw that's flexing, see > http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=47257 >
oh..... oops. I had pictured something more like the first item in this photo: http://en.wikipedia.org/wiki/File:Micrometers.jpg which does indeed let you put a good solid squeeze on your workpiece if you're not careful. > Wow, they're down to $10 each! Indeed -- tx for the link it looks like a useful gadget.
