> How much upward effort does it take to raise just
> one end of a fifteen ton block?
I assume you mean 15-20 ton blocks. And by "raise" you also mean "lift".
> How much lateral effort does it take to roll a
> fifteen ton block?
> Is it 15 tons? or a fraction thereof?
You tell me. And while you are figuring that out, ask yourself what effort is required to drag a 20 ton block flat on the ground compared to the effort of lifting it up a foot or two to get it on a sled and rollers which would therefore exponentially decrease the effort required to drag it in the first place.
> How does a sled running on bedrock reduce the
> amount of effort required to move the block?
> Is the coefficient of friction of the underside of
> a wooden sled less than the underside of a block?
First of all, if the block is not raised its front face will be pulled right into the ground so regardless of the "coefficient of friction" it needs to be raised to be dragged at all.
If you look at the blocks you can see they are quite narrow but also quite deep:
Dragging dozens of blocks like this on the ground in an upright position, i.e. creating the least surface area to drag possible, would obviously be the least practical as toppling would no doubt be a certainty, ironically causing them to have to lift the blocks back again to an upright position, not to mention all of the weight/force would be directed to the smallest possible leading edge which would exponentially increase the problem of driving the block right into the ground when you pulled it.
This leaves the side of the blocks, the widest surface to drag it on the ground, which of course if put on a railed sled would exponentially reduce the drag coefficient. And better yet, put that sled on rollers.
Edited 1 time(s). Last edit at 14-Sep-16 18:19 by Thanos5150.