问题 多选题
如图所示,理想变压器原线圈接u=220sin100πt (V)的 正弦交流电源,图中电流表内阻不计.副线圈接入“110V,60W”灯泡一只,且灯光正常发光.下列说法正确的是(   )

A.电流表的示数为3/11 A

B.通过灯泡的电流的频率为50Hz

C.电流表的示数为3/22 A

D.理想变压器原、副线圈匝数之比为2:1

答案

AB

阅读理解

One day an old man is selling (卖) a big elephant. A young man comes to the elephant and begins to look at it slowly. The old man goes up to him and says in his ear, “Don’t say anything about the elephant before I sell it. Then I will give you twenty dollars.”“All right,” says the young man. After the old man sells the elephant, he gives the young man twenty dollars and says, “Now, can you tell me how you found the elephant’s bad ears?”“I didn’t find the bad ears,” says the young man. “Then why are you looking at the elephant slowly?” asked the old man. The young man answers, “Because I have never seen an elephant before, and I want to know what it looks like.”

根据短文选择正确的答案

(  )11. ________  the elephant.

    A. The young man sells     B. The old man sells

    C. The two men sell        D. The old man buys

(  )12. The young man is looking at the elephant slowly.

He wants to find out ___________.

    A. which foot of the elephant is bad B. how heavy it is

    C. which ear of the elephant is bad D. what it looks like

(  )13. The young man   ______________.

    A. knows the elephant has bad ears B. wants to buy the elephant

    C. looks after the elephant D. gets some money from the old man

(  )14. The young man  ______________.

    A. is not interested in elephants B. knows what an elephant looks like

    C. has seen some elephants before D. has never seen an elephant before

(  )15. Hearing what the young man said, the old man will probably(很可能)be ____________.

    A. angry (生气)      B. happy     C. dangerous      D. hungry

选择题