问题 选择题

一个木块从粗糙的斜面滑下(匀速),则它的(  )

A.机械能和内能都增大

B.机械能增大,内能减小

C.机械能减小,内能增大

D.机械能、内能都不变

答案

木块从粗糙斜面匀速滑下的过程中,质量、速度都不变,动能不变,位置降低,势能减小,故机械能也减小,克服摩擦做功,则内能增加.

故选C.

阅读理解

阅读理解。

     Knowing the best way to study will help you to be a better student. By using your time properly, you

can do your homework more quickly. Learning to study is not difficult.

     The first thing to remember is that you must be willing to learn. It doesn't mean that you must always

like the subject. It does mean, however, that you must be willing to do whatever is necessary to learn. Try

to understand why it is important and how it will help you now and later to do and learn other things.

Knowing mathematics facts will be useful in your whole life. Knowing how to spell makes any kind of

writing easier. Sometimes the subject that you think is going to be uninteresting will be exciting when you

begin to work at it and understand it more clearly. Learning things can be fun if you are willing to work

with them.

    Here's some advice for you: have a certain time each day and a quiet place with good lighting for study, so that you can concentrate on your study without interruptions; have everything ready before you sit

down to study, a dictionary, paper, a pen and books; be sure you understand what you should learn

before you start; read carefully and pay special attention to the most important things; when memorizing,

first find out the main parts and then recite the whole thing; check your homework after you finish it; never

forget the importance of review and preview.

    Don't try to spend a lot of time researching learning methods. There are many students who know many good learning methods but don't study well. They forget that the most useful learning method is to study

hard.

1. The main purpose of the article is______.

A. to prove that learning is not difficult      

B. to make the readers be interested in study

C. to tell the importance of self teaching    

D. to tell the students how to study well

2. The first thing to remember in studying is that ______.

A. you must like the subject              

B. you must follow the teacher

C. you must enjoy learning               

D. you must study hard

3. The following advice is given in the article EXCEPT______.

A. To put a pen, paper and books beside you before study.

B. To study at any possible time and place.

C. To review and preview

D. To pay attention to the most important things.

4. Among the following statements, ______is true.

A. The more learning methods we have, the better we will study.

B. Finding the best learning method is the most important in learning.

C. Knowing good methods, you can't be good at study without working hard.

D. Once we have mastered a good learning method, we can improve our study greatly.

5. From the passage, we can conclude that ______.

A. No pains, no gains        

B. Better late than never  

C. Study comes first          

D. Good methods, good results.

单项选择题

When it comes to suing doctors, Philadelphia is hardly the city of brotherly love. A combination of sprightly lawyers and sympathetic juries has made Philadelphia a hotspot for medical-malpractice lawsuits. Since 1995, Pennsylvania state courts have awarded an average of $ 2m in such cases, according to Jury Verdict Research, a survey firm. Some medical specialists have seen their malpractice insurance premiums nearly double over the past year. Obstetricians are now paying up to $104,000 a year to protect themselves.

The insurance industry is largely to blame. Carol Golin, the Monitor’s editor, argues that in the 1990s insurers tried to grab market share by offering artificially low rates (betting that any losses would be covered by gains on their investments). The stock-market correction, coupled with the large legal awards, has eroded the insurers’ reserves. Three in Pennsylvania alone have gone bust.

A few doctors--particularly older ones--will quit. The rest are adapting. Some are abandoning litigation-prone procedures, such as delivering babies. Others are moving parts of their practice to neighboring states where insurance rates are lower. Some from Pennsylvania have opened offices in New Jersey. New doctors may also be deterred from setting up shop in litigation havens, however prestigious.

Despite a Republican president, tort reform has got nowhere at the federal level. Indeed doctors could get clobbered indirectly by a Patients’ Bill of Rights, which would further expose managed care companies to lawsuits. This prospect has fuelled interest among doctors in Pennsylvania’s new medical malpractice reform bill, which was signed into law on March 20th. It will, among other things, give doctors $ 40m of state funds to offset their insurance premiums, spread the payment of awards out over time and prohibit individuals from double dipping--that is, suing a doctor for damages that have already been paid by their health insurer.

But will it really help Randall Bovbjerg, a health policy expert at the Urban Institute, argues that the only proper way to slow down the litigation machine would be to limit the compensation for pain and suffering, so-called "non-monetary damages". Needless to say, a fixed cap on such awards is resisted by most trial lawyers. But Mr Bovbjerg reckons a more nuanced approach, with a sliding scale of payments based on well-defined measures of injury, is a better way forward. In the meantime, doctors and insurers are bracing themselves for a couple more rough years before the insurance cycle turns.

Nobody disputes that hospital staff make mistakes: a 1999 Institute of Medicine report claimed that errors kill at least 44,000 patients a year. But there is little evidence that malpractice lawsuits on their own will solve the problem.

By mentioning "double-dipping" (Paragraph 4), the author is talking about()

A.compensations

B. premiums

C. stock shares

D. investment