Jeff Liebermann wrote:

Yes, it somewhat depends on thickness. If the
"dent" produce goes though the material and
pops out the other side, you'll get a much
softer measurement than one that does NOT pop
out the other side. Similarly, stacking up
a pile of rubber sheets until the dent is
totally inside the material, will produce
something harder.

For a material M, if you penetrate
1 distance unit at the cost of C, then go on to
penetrate yet another distance unit
(i.e. 2 in total), will the cost then be 2C for
all of that?

Or will the material, altho compromised
(punctated and inflicted degree to some
degree), retain some hindering or
self-enforcing property to make the cost maybe
2^2C instead or something even higher?

Wood for example, with a drill it is perhaps
linear but chop a dagger into it and if it is
thick you won't get anywhere except scratching
the surface.

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