(14分)如图所示,质量M=0.2kg的长板静止在水平地面上,与地面间动摩擦因数

题型:计算题

问题:

(14分)如图所示,质量M=0.2kg的长板静止在水平地面上,与地面间动摩擦因数μ1=0.1,另一质量m=0.1kg的带正电小滑块以v0=8m/s初速滑上长木板,滑块与长木板间动摩擦因数μ2=0.5,小滑块带电量为q=2×10-3C,整个运动过程始终处于水平向右的匀强电场中,电场强度E=1×102N/C,(m/s2)求:

(1)刚开始时小滑块和长板的加速度大小各为多少.

(2)小滑块最后停在距木板左端多远的位置.

(3)整个运动过程中产生的热量.

考点:匀变速直线运动
题型:计算题

下壁右心室梗死

A.V1~V5ST段抬高,异常Q波形成

B.Ⅱ、Ⅲ、aVFST段抬高,异常Q波形成

C.V5~V7、Ⅱ、Ⅲ、aVF、ST段抬高,异常Q波形成

D.Ⅰ、aVLST段抬高,异常Q波形成

E.Ⅱ、Ⅲ、aVF、V3R~V6RST段抬高,异常Q波形成

题型:计算题

斯塔夫里阿诺斯在《全球通史》中写道:“1500年至1763年间,欧洲由于控制了各大海洋和西伯利亚及南北美洲人烟比较稀少的地区,已从默默无闻的地位中崛起。”在此,作者强调了欧洲崛起的

A.市场因素

B.军事因素

C.技术因素

D.政治因素

题型:计算题

Many businesses today use conferences as a means of discussing new plans of the company. As people are paying more attention to the environment and green problems, more businesses are looking for ways to reduce their negative effect on the environment. Many businesses do this by using Web conferencing.

Web conferencing is a technology that allows people to communicate more effectively over the Internet. It’s an easy way of hosting and attending conferences without having to leave the office. Each of the people involved in a Web conference will be posted an invitation to the conference with the time and date of the Web conference on it. When the conference is ready to begin, all participants (参与者) must sit at their computers and they will be connected over the Internet.

With Web conferencing all participants attend conference from the comfort of their own desks. Obviously, in doing this no fuel is used in traveling to and from a conference, and less work is taken up in attending a conference.

Any material to be used during Web conference is simply e-mailed to all the participants before the conference. Participants can then either choose to print material or read it on screen. This not only saves paper but also greatly reduces mailing costs for the business.

As a conference hall or business center isn’t being used, it means that the only power that is used is the power that is used by the participants’ personal computers. Similarly, conference organizers don’t have to arrange for food or overnight accommodation. All this means that less energy is used.

Often in business some companies actively choose to do business with other companies that do many things to reduce their negative impact on the environment. And Web conferencing helps you show other businesses that you are willing to work hard for the green cause.

小题1:What is the passage mainly about?

A.Ways of protecting the environment

B.Green benefits of Web conferencing

C.Ways of hosting a Web conference

D.Impact of Web conferencing on costs小题2:According to paragraph 1, many companies use Web conferencing because they ______.

A.are interested in using any new technology.

B.believe that Web conferencing is more convenient.

C.want to do something to protect the environment .

D.haven’t enough money to hold a traditional conference.小题3:The participants of a Web conference _____.

A.will be e-mailed an invitation before the conference.

B.are required to sit in an office together.

C.will receive many paper materials.

D.must have access to the Internet.小题4:Which of the following words best describes the author’s opinion about a Web conference?

A.Useless

B.Environmentally friendly

C.Inconvenient

D.Money-consuming

题型:计算题

阿托品用于治疗

A.心源性休克

B.过敏性休克

C.失血性休克

D.感染中毒性休克

E.神经源性休克

题型:计算题

当前全国人民为之奋斗的共同理想是()

A.建设中国特色社会主义

B.彻底消灭“三大差别”

C.彻底消灭剥削

D.完全实现人的自由而全面的发展

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