题干

你在上体育课时,遇到了下列一些场景,并由此联想到学过的物理知识,下列联想错误的是(   )

A:“跳远助跑”时利用了惯性的原理

B:“引体向上”时手搓镁粉利用了增大摩擦的道理

C:“踢足球”时利用了力使物体运动状态发生改变的道理

D:“仰卧起坐”时利用了大气压的原理

上一题 下一题 0.0难度 选择题 更新时间:2018-06-05 07:03:40

答案(点此获取答案解析)

D

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任务型阅读

    Recent years have witnessed(见证) the returning of shared bikes across China. Now more and more people choose cycling instead of driving to school, to workplaces or to do sightseeing. Bike-sharing plans are warmly welcomed in many cities. Mobike has 5.85 million active users while Ofo has 1.4 million users this year.

    People can unlock(解锁) the shared bikes by simply using their smartphones. All bikes have GPS and can be left anywhere in public for the next user. They are popular among many Chinese people because they help solve "last-mile" problems in cities. For example, many people find it difficult to get to the hotel when they get off trainers or to travel around the city.

    However, the plans have also led to problems such as illegal(非法的) parking, vandalism(故意毁坏) and theft(偷窃). In February this year, two nurses in Beijing were placed under administrative detention(行政拘留) for five days for putting person locks on two shared bikes.

    In fact, these problems are also shared by bike-sharing plans abroad. Started in 2007, Velib is the largest public bike sharing company in Paries. At its early period, it also met with problems of vandalism and theft. To solve the problem, the company came up with the idea of encouraging(鼓励) people to return the bikes to stations by providing free time for their next rides.

    Now, Chinese bike-shared companies are also trying to solve these problems. For example, Mobike sets a 100-point credit score(信用分数) for each user, but the points will be taken because of his or her bad behaviour. Once a score drops below 80, bike rental(租金) will be increased(增加) from 1 yuan to 100 yuan per 30 minutes.

    Answer the following questions with No More Than 8 Words.