When a table tennis ball falls from a high altitude and reaches the ground, its bounce height is about 0.4 times the drop height. If a table tennis ball falls from a height of 25 meters, it bounces and then falls, and the bounce height is less than 0.5 times when it is bounced many times. rice.
乒乓球从高空下，到达地面后弹起的高度约为落下高度的0.4倍，若乒乓球从25米高处落下，那么弹起后再落下，弹多少次时它的弹起的高度不足0.5米．
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