试题与答案

.同学们利用实验共同验证“杠杆的平衡条件”。实验中使用的杠杆刻线均匀,每个钩码的

题型:实验题

题目:

.同学们利用实验共同验证“杠杆的平衡条件”。实验中使用的杠杆刻线均匀,每个钩码的质量都相等。

⑴杠杆初始状态如图18甲所示,为使杠杆处于水平平衡状态,此时应将杠杆右端的平衡螺母向右调节,也可以将杠杆左端的平衡螺母向________调节。

⑵杠杆调节完毕后,莉莉在杠杆支点两侧挂的钩码如图18乙所示,如果此时莉莉不再支撑杠杆,杠杆不能静止在水平位置。同学们给出了自己的判断和建议:

①小红说,把右侧的钩码减掉一个,杠杆就平衡了。

②小林说,把左侧的钩码向左移动一格,杠杆就平衡了。

③小健说,在左侧的钩码下增加一个钩码,杠杆就平衡了。

④小东说,在右侧的钩码下增加一个钩码,并向左移动一格,杠杆也可以平衡。

你认为都有谁说对了________(填序号)。

 

答案:

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题型:单项选择题

The Bush administration is about to propose far-reaching new rules that would give people with disabilities greater access to tens of thousands of courtrooms, swimming pools, golf courses, stadiums, theaters, hotels and retail stores. The proposal would substantially update and rewrite federal standards for enforcement of the Americans With Disabilities Act, a landmark civil rights law passed with p bipartisan support in 1990. The new rules would set more stringent requirements in many areas and address some issues for the first time, in an effort to meet the needs of an aging population and growing numbers of disabled war veterans.

More than seven million businesses and all state and local government agencies would be affected. The proposal includes some exemptions for parts of existing buildings, but any new construction or renovations would have to comply. The new standards would affect everything from the location of light switches to the height of retail service counters, to the use of monkeys as "service animals" for people with disabilities, which would be forbidden’.

The White House approved the proposal in May after a five-month review. It is scheduled to be published in the Federal Register on Tuesday, with 60 days for public comment. After considering those comments, the government would issue final rules with the force of law. Already, the proposal is stirring concern. The United States Chamber of Commerce says it would be onerous and costly, while advocates for disabled Americans say it does not go far enough.

Since the disability law was signed by the first President Bush, advances in technology have made services more available to people with disabilities. But Justice Department officials said they were still receiving large numbers of complaints. In recent months, the federal government has settled lawsuits securing more seats for disabled fans at Madison Square Garden in New York and at the nation’s largest college football stadium, at the University of Michigan.

The Justice Department acknowledged that some of the changes would have significant costs. But over all, it said, the value of the public benefits, estimated at $ 54 billion, exceeds the expected costs of $ 23 billion. In an economic analysis of the proposed rules, the Justice Department said the need for an accessible environment was greater than ever because the Iraq war was "creating a new generation of young men and women with disabilities". John L. Wodatch, chief of the disability rights section of the Justice Department, said:"Disability is inherent in the human condition. The vast majority of individuals who are fortunate enough to reach an advanced age will benefit from the proposed requirements.

The case of securing more seats for disabled fans is mentioned in Paragraph 4 to()

A. illustrate the Justice Department officials’ heavy burden

B. prove the disabled fans’ enthusiasm for sport-events

C. indicate the low efficiency of modern technology

D. exemplify the inadequacy of the accessible service for the disabled

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