问题 问答题

为什么经典力学只适用于低速运动?

答案

解:经典力学中认为物体的质量是不变的,时间间隔是绝对的,而相对论指出时间间隔是相对的,长度是相对的,物体的质量,随速度增大而增大.在低速运动中,时间间隔、长度、物体质量变化十分微小,经典力学完全适用.

阅读理解

Reading comprehension.

     For almost two months Dominic York, a 23-year-old hairdresser, wandered about hospitals all night,

wearing a white coat and pretending he was a doctor. Yesterday he proudly claimed in court that despite

his complete lack of medical experience or qualifications, he had saved several people's lives. He had even

been allowed to assist a surgeon during an emergency operation on a patient who was about to die on

something she had swallowed.

     "I watched one of those TV dramas about a hospital and suddenly I felt like playing one of the roles

myself. So I put on a white jacket and a stethoscope (听诊器) and walked around one of the biggest hospital

in London. At first I just watched. Once you learn how doctors talk to patients, nurses and others doctors,

it's easy to take people in," he said.

     One of the patients he treated was Laura Kennan. She had been knocked down by a car and fainted.

When she came to in hospital, York was standing over her.

     "He looked very professional. He told me his name was Doctor Simon. Then he gave me some sort of

injection," she said. And then he suddenly cleared off when a nurse asked who he was. She didn't think there

was anything wrong. "I would never have realized he was a fake if a policewoman hadn't showed me his

photograph a week later. When the policewoman told me who he really was, I could hardly believe my cars."

     Judge Raymond Adams told York that he was "shocked and horrified" that he got away with his deceiving

for so long, and then sentenced him to eighteen months in a special prison for criminal with mental disorders.

     "I can only hope that this will not lead to further problems. After all, you will have considerable opportunity

to study the behaviour of the psychiatrists (精神科医生) who will look after you while you are there. If you

try to persuade people that you yourself are a psychiatrist after you are set free, I shall make sure that you

are given a much longer sentence." Judge Adams warned York.

1. York was proud of the fact that _____.

A. a surgeon let him watch an operation

B. he could perform some duties of a doctor

C. he had cheated doctors for so long

D. people thought he could become a real doctor

2. York learned how to behave like a doctor by _____.

A. watching other doctors work

B. talking to doctors and nurses

C. getting some training and experience

D. observing doctors while he was a patient

3. Why was Laura Kennan in hospital? 

A. She had swallowed something and almost died.

B. She had to have and emergency operation.

C. She had been injured in a road accident.

D. She had lost consciousness while driving.

4. The judge's remark implied that York would be more severely punished if he _____.

A. pretended to be a psychiatrist

B. tried to get away from prison

C. was proud of what he had done

D. studied the behaviour of the psychiatrist

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