问题 计算题

我国对家用电冰箱、空调这两个产品率先实施能源效率标识制度,以后生产、销售、进口空调、冰箱均应在显著位置粘贴“中国能效标识”的标签,如图所示.能效标识将能效分为1、2、3、4、5五个等级,等级1表示产品最节能,等级5是市场准入指标,低于该等级要求的产品不允许生产和销售.

(1)图中所示的是两台空调的能效标识,按照图中所给的输入功率,请计算空调A正常工作时的电流是多少安培?(结果保留一位小数)

(2)两台空调的制冷量相同,但能效比却不相同.假设两台空调的使用寿命都为10年,平均每台每年使用600h,请计算使用10年,高效节能空调A比一般节能空调B节约多少千瓦时的电能?每度电按0.8元计算,能节省电费多少元?

答案

解:(1)已知:U=220V  P1=1000W=1KW    P2=1230W=1.23KW    t1=t2=t=6000h

根据公式P=UI得,空调A正常工作时的电流:

I1===4.5A

(2)空调A工作十年消耗的电能:

W1=P1t=1KW×6000h=6000KW·h

空调B工作十年消耗的电能:

W2=P2t=1.23KW×6000h=7380KW·h

使用10年,高效节能空调A比一般节能空调B节约的电能:

△W=W2﹣W1=7380KW·h﹣6000KW·h=1380KW·h

能节省电费:N=0.8元/KW·h×1380KW·h=1104元

完形填空
完形填空。
     A few years ago when my daughter was about two years old, I went through a
difficult time. My husband left us and I didn’t have 1______money. I think I was
also 2______disappointed but I had to take care of my daughter.
     One day I thought I would take my 3______  to a park as she liked to play there
and I thought it was a nice thing to do. I decided to 4_____  there because the bus
was expensive, so it 5_____ us a long time to get there. When we finally  6____,
my daughter immediately began to 7______. She was cold and thirsty and wanted to go
home. I didn’t even have any money to buy a drink 8_____to take the bus back
home. I was so 9______ because my dream of a nice time had fallen apart.
      I started walking back home, and my daughter would not stop crying. I felt so
unhappy and angry with 10____ and my life that I started crying, 11_____.At that
point a car stopped beside us and a gentleman offered us a lift. He took us home,
and seemed really 12______  he even offered me all his change! The kindness of this
stranger really made me feel 13______better. I never saw him again and I don’t
know who he is but he really 14______that day. Now my life is better and my
daughter has 15______  .I always tell her that story. Maybe she doesn’t remember
that day now, but she has been moved by that stranger.
( )1.A. lot of          
( )2.A. a little of    
( )3.A. parents        
( )4.A. drive          
( )5.A. cost            
( )6.A. arrived        
( )7.A. laugh          
( )8.A. and            
( )9.A. excited        
( )10.A. she          
( )11.A. either        
( )12.A. afraid        
( )13.A. much          
( )14.A. helped out me
( )15.A. used up       
B. many        
B. a bit of    
B. son          
B. fly          
B. spent        
B. got          
B. smile        
B. but          
B. angry        
B. myself      
B. also        
B. kind        
B. more        
B. helped me out
B. made up      
C. much            
C. a kind of      
C. daughter        
C. walk            
C. paid            
C. reached        
C. cry            
C. or              
C. happy          
C. I              
C. too            
C. cold            
C. many            
C. broke me down  
C. called up      
D. some            
D. kind of          
D. friend          
D. run              
D. took            
D. be              
D. shout            
D. so              
D. upset            
D. mine            
D. though          
D. serious          
D. lots of          
D. broke down me    
D. grown up        
单项选择题