以下说法正确的有：（） A．加速度不为零的运动，物体的运_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题选择题

以下说法正确的有：（）

A．加速度不为零的运动，物体的运动速度方向一定发生变化

B．加速度不为零的运动，物体的运动速度大小一定发生变化

C．加速度不为零的运动，速度的大小和方向至少有一个要发生变化

D．物体运动的加速度不为零，但速度却有可能为零

答案

CD

匀变速直线运动，速度方向不变，A选项错；匀变速圆周运动，加速度不为零，物体运动的速度大小不变，B选项错；加速度不为零，物体的运动状态一定发生变化，或者速度的大小变化，或者速度的方向变化，或者速度的方向和大小都发生变化，C选项对；自由落体运动，开始下落的瞬间，速度为零，加速度不为零，D选项对。

完形填空

It was a cold winter’s night when I stopped for gas on my way home from work．I was tired and had a slight   36 ．
I worked in a   37  doctor’s office and this was one of those days when the unexpected happened, making the schedule run   38  than usual．It seemed I was going to be late   39  home and my husband, being the   40  person, would be ready to pronounce（宣布） me late once again．Maybe   41  I hurried, I could still make it home．
I was heading inside to   42  for my gas when I noticed an older couple at the counter．I heard them asking for   43  to the local hospital．It was the same hospital that I had just   44  a few minutes ago．
The young man at the counter was trying to be   45  in explaining how to get there, with two other people making   46 ．One of them was   47  trying to give them a whole different route back．It was then that I walked over to the couple and said, “Would you like to follow me to the   48 ?”
A look of   49  crossed the woman’s face．
“I’m going right by there,” I said, which wasn’t a（an）   50  since I had just made up my mind to do   51  that．
I got in my car and began the journey back．I was trying to watch to be sure they were right   52  me．It took only fifteen minutes to get there as rush hour traffic was beginning to   53 ．I felt better than I had all day and my headache was nearly gone．
Later, as I arrived home, my husband   54 , “So you aren’t ever late any more．”
I said, “Sometimes it’s   55  to be late．”

C．experienced

单项选择题

为确定主题达到目标的适宜性、充分性和有效性所进行的活动称为( )。

A．评判

B．验收

C．审查

D．评审