问题 探究题

裘实同学发现一个从斜面滑下来的物体,在水平面上运动的 距离不一定相同,他决定探究这一问题:影响从斜面上滑下来的物体在水平面上运动距离的因素有哪些呢? 他提出猜想一:物体下滑的起点高度; 猜想二:……

(1)请你也提出一个猜想:________________________

(2)请你自选器材,设计一个方案验证裘实的猜想一,并简述

实验结论:______________________________________________________

(3)裘实同学经过实验探究,又推理得出结论:运动物体在水平面上运动的距离与物体的速度和水平面的粗糙程度有关,与物体的质量无关.你认为运动物体在水平面上运动的距离与物体的质量是否有关,并简述理由:_______________________________________________________。

答案

(1)水平面的粗糙程度(或物体的质量)

(2)让同一小球在同一光滑斜面的不同起点高度下滑,比较在同一水平面上运动的距离.物体下滑的起点高度越大,下滑到斜面底端的速度就越大,在同一水平面上运动的距离也就越大

(3)运动物体在水平面上运动的距离与物体的质量无关.物体的速度和水平面的粗糙程度一定时,物体的质量越大,物体所具有的动能越大,但同时摩擦力也越大,由△Ek=Wf易知,s=,即物体运动的距离与质量无关.

阅读理解

阅读理解。

     When I was in Grade Four, Mr Stamps took us to a place called Camp

Noria to go camping.

     When we arrived at the camping, we took a walk in the forest. Then we

had a difficult project: to build a small house in the forest After the project

was finished the sky was dark, then We return to the campsite to have supper.

     We roasted (烤) hotdogs on the bonfire(篝火). The botdogs smelled good! Some of the other food was not that good. After supper everybody played a game of tag(捉人游戏).  It was very cold at night and the next morning

everybody was awake very early.

     Around noon time, the sun rose up. We took turns riding a small horse.

When starting to ride it, I was scared, but after being on it for some time, I

felt that it was fun. In the afternoon we went to row canoes(划独木舟).

Since this was my first time doing these activities, I felt very excited.

     On the third day we returned home. I hope to go back there next year.        

1. How did the writer like the camping?

A. The writer enjoyed it a lot.

B. The writer was afraid of camping.

C. The writer disliked Camp Noria.

D.  It was a little boring.

2. Which of the following activities did the writer and his friends do first

during the camping?

A. Built a small house.    

B. Played a game of tag.

C. Rode horses.        

D. Rowed canoes.

3. What did the writer think of the hotdogs?

A. The writer roasted them.

B. The writer enjoyed them.

C. Not that tasty.

D. They were burned.

4. How long did they camp?

A. Two days.            

B. Three days.

C. Four days.            

D. A week.

5. Which statement is TRUE according to the passage?

A. It didn't take them a long time to build a small house in the forest.

B. All the food they cooked over the bonfire was delicious.

C. It was very cold at night and they all woke up early the next morning.

D.The writer was good at riding a horse and enjoyed it a lot.

名词解释