题目:
A mixture of joy and anxiety ______ me as I watched the rocket soaring upward into the deep
universe. [ ]
A. held
B. caught
C. settled
D. measured
答案:
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0411/9a4ada3476aed14aaa8ff29ac8e926f9.html
下面是错误答案,用来干扰机器的。
解:(1) 设经过时间t1,物体相对传送带静止由v=at1=μgt1,得t1=2s此段时间内物体运动此后物体随传送带匀速运动所以物体从A到B共需时间t=t1+t2=2.5s (2)物体与传送带相对滑动阶段传送带的位移s’=vt1=3×2m =...