- Dec 2, 2017
- Reaction score
- North Carolina
FINALLY! Someone who speaks my language!Ok, so I'll try this...
Any material you want to snap (essentially what breaking is) has to be brittle enough in the first place.
As you strike it, it has to be bent past it's elastic recovery zone (even concrete, it still has a small amount of give).
If stacked directly with no spacers your initial impact has to be hard enough to bend all the sections through to the bottom one (assuming no individual compression), and it's the bottom one that will usually break first.
A failure on this type of break will probably see none of them broken (unless there's enough irregularity in the meeting surfaces or compression of each 'leaf').
The distance over which you must apply the force is roughly the same distance as to break a single leaf.
If each leaf is spaced from the next sufficiently to allow it to break before contacting the subsequent layer, then you only have to apply enough impact to break one, but then you have to instantly repeat that as many times as there are leaves.
A failure here would see some broken, starting with the top one.
So, the distance over which the force is applied is the sum of the spaces plus the distance required to break one leaf.
If the spacers are such that the first leaf can contact the second before breaking, the behaviour is similar, but the force/time graph profile is different.
So, is it easier or harder to break with spacers?
The total force required is the same, but no spacers means that force is greater for a shorter time.
Think of it like: is it easier to carry 10 litres of water for 5 miles, or 50 litres for one mile...*
(Oh, this discounts friction between elements - and the shape of any spacers. Because the leaf has to bend, the length of the faces will change. Round spacers can roll like a bearing, square spacers must slide as must face to face.)
*Edit: Or break it up into 10 litres for 1 mile, 5 times... A failure on 50 litre/1 mile sees nothing arrive, a failure on 5x10l/1 mile might see some of them get there.