A karate player suddenly reduces the speed of his hand while striking a tile. Explain why?

Explanation:

The karate player strikes the slab of ice as fast as possible with his or her hand. In doing so, the entire momentum of the hand is reduced to zero in a very short time. As a result, the force delivered on the pile of tiles or a slab of ice is large enough to break it.

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answer///terminator or twilight zone;