试题与答案

下列各种摩擦中，属于有害摩擦的是，属于有益摩擦的是 。 ①机器运转时，各部件之间

来源：www.tikuol.com
题型：填空题

题目：

下列各种摩擦中，属于有害摩擦的是                              ，属于有益摩擦的是                              。

①机器运转时，各部件之间的摩擦

②拔河比赛时，手与绳之间的摩擦

③汽车行驶时与空气之间的摩擦

④吃饭时，筷子与食物之间的摩擦

答案：

①③，②④

考点：摩擦力的种类
试题推荐
题型：阅读理解
阅读理解。
Welcome to the zoo
     Come and meet the Indian (印度的) elephants and the new tigers from America. The bears are
waiting to meet you, and the monkeys from China are waiting to throw things at you. The lovely dogs
from Australia are waiting to laugh at you. The giraffes from Zambia are waiting to look down on.
TicketsOpening time
Adults:＄2.00
Children:＄1.00
Under 12: Free           		Friday,
10:00a.m----3:00p.m.  
The other days
9:00a.m----4:00p.m.             
Keep the zoo clean!
Do not touch, give food to or go near the animals.
根据短文内容完成选择。
1. How many kinds of animals are talked about in the passage?
A. Four        
B. Five
C. Six          
D. Seven
2. Now Mr. Smith is in the zoo with his two sons, one aged 14 and the other 10. How much are the
    tickets altogether (总共)?
A. ＄4.00      
B. ＄2.00    
C. ＄3.00      
D. ＄1.00
3. Which of the following is a visiting time?
A. 8:30 a.m. Monday.            
B. 9:30 a.m. Friday.
C. 5:00 p.m. Tuesday.            
D. 2:00 p.m. Sunday.
4. From the passage we can guess the animal "giraffe" must be very _____.
A. fat
B. long          
C. tall        
D. strong
5. Which of the following can we do in the zoo?
A. Take a few nice photos.
B. Give some food to the fish
C. Touch the monkey on the head.
D. Throw things everywhere.
查看答案
微信公众账号搜索答案