问题 实验题

(5分)某同学在做多用电表测电阻的实验中:

  

(1)测量某电阻时,用“×10W”档时发现指针偏转角度过大,他应该换用_____档(填“×1W”或“×100W”),换档后,在测量前先要______________。

(2)如图所示,A、B、C是多用表在进行不同测量时,转换开关分别指示的位置,D是多用表表盘指针在测量时的偏转位置。

若是用A档测量,指针偏转如D,则读数为________;

若是用B档测量,指针偏转如D,则读数为_______;

若是用C档测量,指针偏转如D,则读数为_______。

答案

(1)´1 ,重新调零 (2) , 6.4mA , 32.0 V

分析:指针偏角大,应换用小倍率,并重新调零,电阻的读数为示数乘以倍率,电压和电流的读数为格子数乘以每小格表示的数.

解答:解:(1)指针偏角过大,说明待测电阻阻值较小,为了准确要换×1挡,然后重新调零.

(2)若用A挡,是测电阻,读数为13×100=1.3×103Ω

若用B挡,是测电流,读数为32.0×=6.40mA

若用C挡,是测电压,读数为32.0×=32.0V

故答案为:(1)×1,重新调零  (2)1.3×103Ω,6.40mA,32.0 V

点评:本题考查了欧姆表、电压表和电流表的使用和读数,记住其方法即可解决此类题目

完形填空
Chose the best answer from A、B、C or D to complete the passage.
       Around the world, people have different ideas about what good manners are.
       When you go go restaurants in different parts of the world, it's     1     to know the right and wrong
things to do. For example, in China it's OK to     2     a lot of noise in a restaurant. In fact, if a restaurant
isn't noisy and     3   , you may think there's something wrong with it. However, in many western countries,
restaurants are     4    palces. If a table is too loud, other people who are eating there might even    5    to
the owner of the restaurant.
       Paying the bill is also different from country to country. In China, one person usually pays for     6   .
In western countries, one person pays if he or she is entertaining clients, but     7    friends eat together,
they usually share the cost. This is called "Going Dutch" Also, when westerners pay the bill, they ususlly
leave some money for the     8   . This is called "leaving a tip." Leaving a tip is thought to be polite. In the
US, it's     9    to leave tips of 10%, 15% or 20% of the bill. Which is decided by how good the service is.
Good waiters can make a lot of money! 
       The way people eat food is different in the world, but you can    10   the same kinds of food in many
countries. Chinese and Italian food, for example, are popular all over the world.
( )1.A.popular  
( )2.A.cause    
( )3.A.lively     
( )4.A.noisy    
( )5.A.shout    
( )6.A.everybody 
( )7.A.until    
( )8.A.gatekeeper
( )9.A.terrble  
( )10.A.invent  
B.difficult
B.keep    
B.friendly
B.quiet  
B.explain  
B.nobody 
B.when    
B.seller  
B.common     
B.discover      
C.important 
C.hear        
C.lucky         
C.busy      
C.complain     
C.somebody  
C.unless     
C.waiter     
C.serious      
C.prefer          
D.enjoyable
D.make       
D.polite       
D.clean    
D.speak        
D.none     
D.since      
D.visitor    
D.unusual               
D.find       
填空题