问题 填空题

在做“用单摆测定重力加速度”的实验中,某同学用毫米刻度尺测得摆线长L0=945.8mm;用游标卡尺测得摆球的直径如图甲所示,则摆球直径d=______mm;用秒表测得单摆完成n=40次全振动的时间如图乙所示,则秒表的示数t=______s;若用给出的各物理量符号表示当地的重力加速度g,则计算g的表达式为______.

答案

直径读数:

主尺:20mm,游标尺对齐格数:4个格,读数:4×0.05=0.20mm,所以直径为:20+0.20=20.20mm;

秒表读数:

大盘读数18.4s,小盘读数60s,故时间为78.4s;

根据T=2π

L
g
、t=nT、L=L0+
d
2
,得:g=
4π2n2(L0+
d
2
)
t2

故答案为:20.20,78.4,

4π2n2(L0+
d
2
)
t2

阅读理解

阅读理解。

     On Christmas morning, I went to the Cockhedge Mall. People there were all busy buying their last

minute requirements. I needed to buy a birthday card for my son-in-law whose birthday is the 29th of

December. Picking up a few more things as well as my cared I went to join the line for the express

checkout which was for people who only had a few items in a basket and not a trolley load. This line

was next to the Customer Service desk.

     Seemingly waiting quite a long time, I was jogged out of my thoughts by a voice behind me making

comments on the things I bought.

     It was so funny when I realized that she was describing the contents of my basket. The owner of the

voice was a very pretty young lady. I said to her that I was going to buy a box of Christmas cookies but

the only ones left were not to my liking. The lady told me that just opposite Cockhedge in Superdrug they

had lots of cookies. I said, "I'm not going to bother now. I had enough of shops and I'm going home."

     The assistant from the Customer Service came across at this time saying"If there is anyone in the line

with a few items in their basket, none of which needed to be weighed, I will check out their groceries at

the desk." Because I had the sprouts (豆芽菜) which needed to be weighted, the young lady accepted the

offer and walked away waving goodbye.

     Eventually my turn came at the checkout. I was walking away when I met my new friend once again

who handed me a beautiful box of Christmas cookies. With a big hug she said "Hope you have a lovely

Christmas." She had been into Superdrug to buy me the cookies while I was still queuing in Cockhedge.

     What a generosity to a stranger! I was so surprised you could have knocked me down with a feather.

My Good Samaritan would never know what a joyful Christmas day I had with my family. Telling them

this story, as we ate around the table, kept everyone spellbound.

1. The underlined word "spellbound" in the last paragraph probably means _____.

A. interested

B. disappointed

C. astonished

D. frightened

2. Which of the following could be the best title of the story?

A. A Piece of Lucky Feather

B. A Surprise Christmas Gift

C. The Boring Shopping Experience

D. The Unforgettable Big Hug

3. How does the writer feel about the pretty young lady?

A. Worried.

B. Satisfied.

C. Grateful

D. Proud. 

4.What can we learn from the story?

A. Nobody is sure what will happen the next moment.

B. A simple action can bring other people happiness.

C. Being patient will decrease the waiting time.

D. Life without hope and faith is a full thing.

单项选择题