a subway train starting from rest along a straight track has

来源：学生作业帮编辑：大师作文网作业帮分类：英语作业时间：2024/11/13 17:09:50

a subway train starting from rest along a straight track has a uniform acceleration of 1.8m/s2 for the first 20m it travels.
a.calculate its speed when it has traveled 10m.
b.When it has traveled 20m,will its speed be less than double,double,or more than double its speed at 10m?
c.Now calculate its speed when it has traveled 20m .Does this agree with you answer B

题目说的是火车从静止开始做加速度1.8m/s^2的直线运动.
1.计算10m时的速度
2.当运行了20m,火车的速度和10m的2被什么关系、大于?小于?
3.计算20m的速度,是否和你在2中选择的一样.
S=Vt^2/2a
10m时候的速度Vt=6m/s
20m时候速度Vt=6√2m/s
20m的速度比10m速度的2倍小

a subway train starting from rest along a straight track has take the subway/train还是take a subway/train take the subway ,take the train 能不能说成take a subway ,take a t 英语翻译Atrain travels in uniform motion along a straight level 关于英语冠词的问题 take the train/subway 说take a train/subway 就很奇怪..但英语翻译A 0.48 kg block slides along a small track with elevated Is this the train station or subway station?This is a train 选择最恰当的答案1.Has the train from Beijing _________ yet?A.reached 英语翻译The bullet train D106 from Changsha to Shanghai has a sh The train is starting ___A__five minutes.A in B at C for D s a figure that can be folded over along a straight line so th SEX TIPS FOR STRAIGHT WOMEN FROM A GAY MAN怎么样