题干

为了探究功与速度变化的关系,现提供如图1所示的器材,让小车在橡皮筋的作用下弹出后,沿木板滑行,请思考探究思路并回到下列问题,(打点计时器所接交流电频率为50Hz)

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同类题1

阅读下列材料,回答问题。

材料一:香港的水坑口街(原名叫“波些臣街”“占领街”)……这标志着中国半殖民地半封建社会的开始,也是血泪斑斑的中国近代史的开始。那片美丽的香港海湾被冠以维多利亚女王的名字,以纪念英国对一个古老文明的胜利。                                             ——《复兴之路》解说词

材料二:昨日下午,法国皮诺家族在国家博物馆将圆明园流失文物青铜鼠首和兔首无偿捐赠给中国,这是圆明园被劫掠文物首次以无偿捐赠的方式回归。国家文物局已将这两尊兽首划拨国家博物馆收藏,并将于近期公开展出。至此,圆明园12兽首中已有7件回归。

——《新京报》2013年6月29日

材料三:清国之败,非君相一己之罪,盖其墨守常经,不变通所致也。夫取士必考试,考试必由文艺,文艺乃为显荣之阶梯,岂足济实效乎? ……前三十载,我日本之国事,遭若何等之辛酸,厥能免于垂危者,度阁下之所深悉也。当此之时,我国去旧治,因时制宜,更张新政,为国可存立之一大要图。……——摘自1895年《大日本海军总司令官伊东佑亨致大清国北洋水师提督丁汝昌书》

材料四:结果京师再陷,朝廷狼狈出亡,东北初步全部沦陷,被据五年,结果赔偿巨款,京津一带驻兵,形同异域,满清政府完全在外人宰制之下,中国已失去独立的精神。

——郭廷以《近代中国的变局》请回答:

同类题3

阅读理解

    If you are interested in studying at an American university, you have to take the Test of English as a Foreign Language. The test is widely known as the TOEFL. It is the most widely used language exam for American universities.

    There are two major kinds of the TOEFL test. The first is the IBT,or Internet based Test. It is offered in most of the world and accepted by nearly every university and scholarship program in the United States. The other kind of the test is called the Paper­based Test or PBT. The PBT is less costly to take and does not require use of the Internet.

    But how to get started with TOEFL? Here are some tips.

    ⒈Plan ahead — It takes a long time to improve your TOEFL score. Do not expect a big lift in your test results after two weeks. You will have to spend a lot of time and energy.

    ⒉Master the basics first — You should have to be good at basic English before you take the test. If you score below 500 on the PBT or 70 on the IBT, study for a few months and come back to the TOEFL later.

    ⒊Get a study guide — It is easy to find study guides for the IBT. Pearson, Barron's, ETS, and Kaplan all produce quality materials, take a practice test once or twice a month. The best study guides will have explanations in the answer key.

    ⒋Use outside resources — Remember, you are learning a language, not a test. You can improve your TOEFL score by making English part of your daily life. Some simple ways are listening to English speakers, watching movies and reading newspapers. Some others are reading English textbooks, sending and reading text messages in English, and writing online in English.

    The best way to do well on the TOEFL is to know English well. The real goal of the test is to measure how well a student can communicate in English­speaking classroom.

    If you want to know more, please click here.

同类题4

阅读理解

      The Internet, mobile phones and Ipads are part of our lives now. Technology is greatly affecting all ways of our lives, from the ways we work to the ways we play. And it even causes a number of social problems such as cloning humans.

      We have had lots of technology and it has changed our lives a lot. There is no doubt that humans will continue to use more and more technology. Here are some examples of modern technology that will change our ideas and will affect our lives greatly.

     Global positioning system (GPS) (全球定位系统)

      It's a system that uses radio signals from satellites to show exact information. It tells you where the user is on the earth in all weather conditions. It's made up of three parts: satellites, control equipments(设备) on land and receivers.

     Space Technology

      Russian and American scientists have worked together for the international Space Station (ISS) for a long time. They hope the ISS will provide a long-lasting lab. Such a lab will bring humans limitless (无限的) advantages. It's even hoped that one day space technology will take humans to their new houses in space.

     Underwater Robot

     Hercules is a kind of underwater robot with some high technology equipments. It will be used to look for ancient ships which were destroyed into the deep sea during their journey long ago.

     The world is changing so quickly that it's hard for us to catch up with all the new inventions because they seem to come out every month. It's important for us to learn about new technology and the role that it plays in our lives. So we should be willing to accept modern technology, or we will fall behind the times.