Selective Breaking

[kungfu-photomaster]

This question was really for Dr. Yang, Jwing-Ming (given his vast knowledge of physics and kung fu).

In "selective breaking,"were a practitioner can break the middle or bottom or three concrete blocks (after striking the top block; sending energy down into the blocks below).

How is this break possible according to Newtonian physics and/or quantum physics? (Assuming no trickery and with the blocks/bricks all being identical taken from the same batch stacked on top of one another without spacers). --Yes I know Yi, Qi, and Jin (I'm looking for a scientific answer)...
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