当我们坐在电视机前欣赏斯诺克比赛时,常常为运动员的精彩表现惊叹不已!母球在球杆的撞击下,能够准确地把目标球撞进袋中,宛如有一只看不见的手在操纵着这一切!甚至当运动员击球后,母球竟然像中了魔法一样,又奇迹般地滚回到原来的出发点,产生一种神奇的“缩杆”现象!这究竟是什 When we sit in front of the TV and enjoy the snooker game, we often marvel at the wonderful performance of the athlete! The cue ball hits the target ball accurately in the bag, like an invisible hand. In the manipulation of all this, even when the athlete hits the ball, the cue ball actually looks like a magic, and miraculously rolls back to the original starting point, resulting in a kind of magical “contract” phenomenon! What is this?