兰州七里河区初三全日制冲刺集训

新一轮 复习备考周期正式开始， 为各位初三考生整理了各学科的复习攻略，主要包括中考必考点、中考常考知识点、各科复习方法、考试答题技巧等内容，帮助各位考生梳理知识脉络，理清做题思路，希望各位考生可以在考试中取得优异成绩!下面是《 物理知识点：电流的磁场》，仅供参考!

电流的磁场

奥斯特实验：通电导线的周围存在磁场，称为电流的磁效应。该现象在1820年被丹麦的物理学家奥斯特发现。该现象说明：通电导线的周围存在磁场，且磁场与电流的方向有关。

通电螺线管的磁场：通电螺线管的磁场和条形磁铁的磁场一样。其两端的极性跟电流方向有关，电流方向与磁极间的关系可由安培定则来判断。

冲刺题重点归纳

( ) 1. Where Uncle Sun yesterday?

A. was B. were C. did D. does

( ) 2. They going to see Mr. Sun tomorrow.

A. is B. are C. am D. be

( ) 3. Some are in the river and some are games.

A. swiming, playing B. swimming, playing

C. swimming, playing D. swimming, playing

( ) 4. Where is Dick? He to the reading-room.

A. has been B. went

C. has gone D. goes

( ) 5. Mark Twain, an American writer, everybody here.

A. knows B. is known as

C. is known to D. is known for

( ) 6. I hope he will come to see me before he here.

A. leave B. leaves C. will leave D. left

( ) 7. My teacher told me that Australians English.

A. spoke B. speak

C. speaks D. are speaking

( ) 8. I think she right now.

A. reading B. reads C. is reading D. read

( ) 9. ---- Where are the children?

---- They a good time in the garden.

A. are having B. have C. have had D. had

( ) 10. ----- Where my glasses? I can’t find them.

---- I them on the bookshelf, but they aren’t there.

A. you put, put B. you have put, have put

C. have you put, put D. did you put, have put

( ) 11. When the police arrived, the man for 10 minutes.

A. died B. was death

C. had died D. had been dead

( ) 12. By the time this talk is over, we a lot about the earth.

A. will be learning B. are learning

C. world learn D. will have learnt

( ) 13. The teachers told me that they me to smooth away the difficulties.

A. helped B. will help C. help D. were going to help

( ) 14. ----Have you seen him today?

----Yes, I him this morning.

A. has seen B. see C. will see D. saw

( ) 15. He worried when he heard this news.

A. is B. was C. does D. did

( ) 16. What’s your friend going next week.

A. doing B. do C. does D. to do

( )17. I don’t think that it’s true. He’s always strange stories.

A. tell B. telling C. told D. tells

( ) 18. Have you ever West Hill Farm?

A. gone to B. arrived C. come to D. been to

( ) 19. How long he the novel?

A. has, borrowed B. has, kept

C. has, lent D. is, using

( ) 20. He to do this lessons at eight every evening.

A. is begining B. is beginning

C. begin D. begins

( ) 21. The children a swim this afternoon.

A. are going to has B. is going to have

C. are having D. are going to have

( ) 22. There a telephone call for my brother Steven yesterday.

A. is B. are C. was D. were

( ) 23. he on well with his friends this term?

A. Does, gets B. Does, get

C. Is, getting D. Is, geting

( ) 24. Who away my pen? I can’t find it.

A. haven taken B. takes C. has taken D. took

( ) 25. Shall we football this Saturday?

A. play B. playing C. plays D. to play

( ) 26. The children at school now.

A. is B. are C. was D. were

( ) 27. Mr. Smith short stories, but he a TV play these days.

A. is writing, is writing B. is writing, writes

C. writes, is writing D. writes, writes

( ) 28. He said he the league for two years.

A. has joined B. has been in

C. had been in D. joined

( ) 29. She likes watering trees in the garden, she?

A. doesn’t B. don’t

C. isn’t D. didn’t

( ) 30. What you to do to keep the room clean?

A. do, have B. does, have

C. did, have D. are, have

( ) 31. Some flowers by Kate already.

A. have been watered B. watered

C. have watered D. has been watered