【简答题】某质点作简谐运动,周期为2s,λ=2m,振幅为0.06 m,t=0 时刻,质点恰好处在平衡位置且向正向位移运动。若此振动向x轴正向传播,则此振动形成的一维简谐波的波动表达式为()
【单选题】某质点作简谐振动,周期为2s,振幅为0.06m,计时开始时(t=0),质点恰好在负向最大位移处,若此波一u=2m/s的速度向x轴正向传播,则此波的方程为 [ ]
A.
x=0.06cos[ p(t- x/2 )+p ]
B.
x=0.06cos[ p(t+ x )+p ]
C.
x=0.06cos[ p(t- x )+p ]
D.
x=0.06cos[ p(t+ x/2 )+p ]
【判断题】____猪瘟肠道“扣状溃疡”病变,是纤维素性浆膜炎引起的。P32
【简答题】某质点作简谐振动,周期为 2s ,振幅为0.06m ,t=0 时质点恰好处在负向最大位移处,求:1 该质点的振动方程;2 此振动以波速u=2m/s 沿x 轴正方向传播时,形成的一维简谐波的波动表达式(以该质点的平衡位置为坐标原点);3 该波的波长。
【单选题】某 web 站点目录为 C:\myweb , IP 地址为 192.168.1.3 ,主机名为 Webserver ,内网域名为 www.abc.com ,虚拟目录的站点路径为 c:\myweb\bumen ,虚拟目录别名为 department ,下面可以访问虚拟目录下 index.htm 的 URL 是( )。
A.
http://192.168.1.3/department/index.ht m
B.
http://www.abc.com/bumen/index.ht m
C.
http://webserver/department/index.ht m
D.
http://www.abc.com/bumen/index.ht ml
【单选题】法乐四联症患儿哭闹时突然发生昏厥、抽搐的原因是:
【简答题】In recent years, more and more college students have been working in their spare time. Some people think it affects students' study; also many argue that it can improve their competence. What's your o...
【单选题】In recent years there has been an increasing number of large oil spills. These spills, some of which have occurred directly at the site of extraction and others during transportation, have had in adve...
C.
The Effect of Oil on Marine Organisms.
D.
The Study of Oil Spills.
【单选题】绝缘子发生沿面放电时闪络电压由大到小依次排列为