“蹦极”就是跳跃者把一端固定的长弹性绳绑在踝关节等处,从几十

蹦极就是跳跃者把一端固定的长弹性绳绑在踝关节等处,从几十米高处跳下的一种极限运动。某人做蹦极运动,所受绳子拉力F的大小随时间t变化的情况如图所示。将蹦极过程近似为在竖直方向的运动,重力加速度为g。据图可知,此人在蹦极过程中最大加速度约为

Ag              B2g       

C3g             D4g

 

 

 

 

 

 

 

 

 

 

 

 

 

答案

B

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