如图所示,在光滑水平面上运动的物体,刚好能越过一个倾角为α的固定在水平面上的光滑

题型:多选题

问题:

如图所示,在光滑水平面上运动的物体,刚好能越过一个倾角为α的固定在水平面上的光滑斜面做自由落体运动,落地时的速度为v,不考虑空气阻力及小球滚上斜面瞬间的能量损失,下列说法正确的是

[ ]

A.小球冲上斜面前在水平面上的速度应大于v

B.小球在斜面上运动的时间为v/gsinα

C.斜面的长度为v2/2gsinα

D.小球在斜面上运动的加速度大于gsinα

考点:机械能守恒定律
题型:多选题

新认定为一般纳税人的小型商贸批发企业实行纳税辅导期管理的期限为()

A.3个月

B.6个月

C.12个月

D.36个月

题型:多选题

— What’s your hobby, Jack?

— I like playing football ______ listening to music.

A.as well as

B.as good as

C.such as

D.as a result

题型:多选题

下列政府机构中,实行“双重领导关系”的有( )。

A.民政机关

B.派出机关

C.公安机关

D.土地管理机关

题型:多选题

阅读理解.

     Since the 1970s,scientists have been searching for ways to link the brain with computers.

Braincomputer interface (BCI) technology could help people with disabilities send commands

to machines.

     Recently,two researchers,Jose Millan and Michele Tavella from the Federal Polytechnic

School in Lausanne,Switzerland,demonstrated(展示)a small robotic wheelchair directed by

a person's thoughts.

     In the laboratory,Tavella operated the wheelchair just by thinking about moving his left or

right hand.He could even talk as he watched the vehicle and guided it with his thoughts.

     "Our brain has billions of nerve cells.These send signals through the spinal cord(脊髓)to

the muscles to give us the ability to move.But spinal cord injuries or other conditions can

prevent these weak electrical signals from reaching the muscles,"Tavella says."Our system

allows disabled people to communicate with external world and also to control devices."

     The researchers designed a special cap for the user.This head cover picks up the signals

from the scalp(头皮)and sends them to a computer.The computer interprets the signals and

commands the motorized wheelchair.The wheelchair also has two cameras that identify objects

in its path.They help the computer react to commands from the brain.

     Prof.Millan,the team leader,says scientists keep improving the computer software that

interprets brain signals and turns them into simple commands."The practical possibilities that

BCI technology offers to disabled people can be grouped in two categories:communication,

and controlling devices.One example is this wheelchair."

     He says his team has set two goals.One is testing with real patients,so as to prove that this

is a technology they can benefit from.And the other is to guarantee that they can use the

technology over long periods of time.

1.BCI is a technology that can ________.

A.help to update computer systems

B.link the human brain with computers

C.help the disabled to recover

D.control a person's thoughts

2.How did Tavella operate the wheelchair in the laboratory?

A.By controlling his muscles.

B.By talking to the machine.

C.By moving his hand.

D.By using his mind.

3.Which of the following shows the path of the signals described in Paragraph 5?

A.scalp→computer→cap→wheelchair

B.computer→cap→scalp→wheelchair

C.scalp→cap→computer→wheelchair

D.cap→computer→scalp→wheelchair

4.The team will test with real patients to ________.

A.make profits from them

B.prove the technology useful to them

C.make them live longer

D.learn about their physical condition

5.Which of the following would be the BEST title for the text?

A.Switzerland,the BCI Research Center

B.New Findings about How the Human Brain Works

C.BCI Could Mean More Freedom for the Disabled

D.Robotic Vehicles Could Help to Cure Brain Injuries

题型:多选题

王父向其子王某提起追索赡养费的诉讼,经法院传票传唤,在开庭时王某无正当理由未出庭,此时,法院应当如何处理( )

A.对王某进行拘传
B.缺席判决
C.延期审理
D.诉讼中止

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