试题与答案

一足够长水平浅色传送带以V0匀速运动,现将一可视为质点的小煤块轻放在其上方,已知

题型:问答题

题目:

一足够长水平浅色传送带以V0匀速运动,现将一可视为质点的小煤块轻放在其上方,已知煤块与传送带间的动摩擦因数为μ.经过一定时间后达到共同速度.令传送带突然停下,以后不再运动,到最后煤块也停下.已知重力加速度为g.求:

(1)煤块第一次达到与传送带相对静止所用的时间;

(2)煤块在传送带上划出的痕迹长度.

答案:

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67-71: CBADC 

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题型:阅读理解

阅读理解。

    Studies have shown it takes a doctor about 18 seconds to stop a patient after he begins talking. 

    It was Sunday. I had one last patient to see. I came close to her room in a hurry and stood at the doorway.

She was an older woman, sitting at the edge of the bed, trying to put socks on her swollen(肿大的) feet. I

spoke quickly to the nurse, saw her chart saying she was in stable(稳定的) condition. I was almost in the

clear. 

   She asked if I could help put on her socks. Instead, I began a long speech that went something like this:

" How are you feeling? Your blood sugar and blood pressure (血压)were high but they're better today. The

nurse said you can't wait to see your son who's visiting you today. It's nice to have a family visit from far

away. I'm sure you really look forward to seeing him. "

    She stopped me with a serious voice. " Sit down, doctor. This is my story, not your story. "

    I was surprised and ashamed. I sat down. I helped her with the socks. She began to tell me that her only

son lived around the corner from her, but she had not seen him in five years. She believed that the pressure of

this caused greatly to her health problems. After hearing her story and putting on her socks, I asked if there

was anything else I could do for her. She shook her head and smiled. All she wanted me to do was to listen.

     Listening to someone's story costs less than expensive diagnostic(诊断的) testing but is key to healing

(痊愈).

     I often thought of what that woman taught me the importance of stopping, sitting down and truly listening.

And, not long after, unexpectedly, I became the patient, with a diagnosis of sclerosis(硬化症) at age 31. Now,

 20 years later, I sit all the time in a wheelchair.

     For as long as I could, I continued to see patients from my chair, but I had to give up my job when my

hands were influenced. I still teach medical students and other health care professionals, but now from the view

of doctor and patient.

    I tell them I believe in the power( 力量) of listening. I tell them I know firsthand that huge healing takes place within me when someone stops, sits down and listens to my story.  

1. What does"I was almost in the clear" mean?

A. I thought everything was clear.

B. I was about to finish my work.

C. I almost made myself understood.

D. I was very quickly out of her sight.

2. From the 4th paragraph, we can infer the woman ___from the way she said.

A. showed her anger and impatience

B. refused to listen to the doctor

C. liked giving orders to people

D. could not wait to break in

3. What is the best title of the passage?

A. Listening-a Powerful Medicine

B. An Unforgettable Experience

C. A Lesson Given by a Patient

D. Care—a Key to Treatment .

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