您所在的当前位置：初中物理试题 >

速度与机械运动

> 气象观测站测得今日是北风，风速是5m/s，某同学看到一列沿直线行驶的火车，车头上冒出的烟是竖直上升的，则 A.这列火车正在向北行驶 B.这列火车正在向南行驶 C.这列火车向北行驶的速度是18km/h D.这列火车向南行驶的速度是18km/h

问题：

发布时间：2024-09-13

气象观测站测得今日是北风，风速是5m/s，某同学看到一列沿直线行驶的火车，车头上冒出的烟是竖直上升的，则

A.这列火车正在向北行驶
B.这列火车正在向南行驶
C.这列火车向北行驶的速度是18km/h
D.这列火车向南行驶的速度是18km/h

参考答案：

提问用户：da***0sM

可能感兴趣的题目：

1 下列有关3S技术运用的叙述，正确的是 A．运用RS可以确定110巡逻车的位置 B．运用RS可以获取水灾淹没区域的动态信息 C．运用GIS可以确定运钞车位置 D．运用GIS可以获取森林火场遥感信息
2 求三个不相等的实数a，b，c最大值的程序框图如图所示，则空白判断框内应为（　　） A．a＞b？ B．a＞c？ C．d＞b 或 a＞c？ D．a＞b 且 a＞c？
3 已知向量，满足且则与的夹角为 A． B． C．　 D．
4 完形填空。 I first went to hear a live rock concert when I was eight years old. My brother and his friends were all 1 of a heavy metal group called Black Wednesday. When they 2 that Black Wednesday were going to perform at our local theatre, they all bought 3 for performance. However, at the last minute, one of the friends couldn"t go, so my brother 4 me the ticket.I was really 5 ! I remember the buzz (嘈杂声)of excitement inside the theatre as we all found our 6 . After a few minutes, the lights went down and everybody became 7 .I could barely make out the stage in the 8 . We waited. Then there was a roar from the crowd, like an explosion, as the first members of the band 9 the stage. My brother leaned over and shouted something in my ear, but I couldn"t 10 what he was saying. The first song was already starting and the music was as 11 as a jet engine.I could 12 the drum beats and bass notes in my stomach. I can"t recall any of the songs that the band played. I just 13 that I really enjoyed the show and didn"t want it to 14 . But in the end, after three encores (加演), the show finished. We left the 15 and walked unsteadily out onto the pavement.I felt a little dizzy, as if I had just 16 from a long sleep. My ears were still 17 with the beat of the last song. After the 18 , I became a Black Wednesday fan too for a few years before getting into other kinds of music. Once in a while, 19 , I listen to one of their songs and 20 I"m back at that first show. ( )1. A. members ( )2. A. guessed ( )3. A. flowers ( )4. A. booked ( )5. A. relaxed ( )6. A. seats ( )7. A. comfortable ( )8. A. silence ( )9. A. fell upon ( )10. A. forget ( )11. A. loud ( )12. A. feel ( )13. A. realize ( )14. A. continue ( )15. A. party ( )16. A. escaped ( )17. A. aching ( )18. A. competition ( )19. A. though ( )20. A. decide B. friends B. discovered B. drinks B. offered B. embarrassed B. entrance B. quiet B. noise B. got through B. hear B. heard B. touch B. understand B. delay B. theatre B. traveled B. burning B. performance B. otherwise B. regret C. fans C. thought C. clothes C. returned C. excited C. spots C. senous C. darkness C. broke into C. repeat C. sweet C. enj oy C. believe C. finish C. opera C. benefited C. ringing C. interview C. instead C. conclude D. volunteers D. predicted D. tickets D. found D. encouraged D. space D. nervous D. smoke D. stepped onto D. bear D. fast D. digest D. remember D. change D. stage D. woken D. rolling D. celebration D. besides D. imagine
5 设函数 f(x)=cos(2x+ π 3 )+1，有下列结论： ①点 (- 5 12 π，0)是函数f（x）图象的一个对称中心； ②直线 x= π 3 是函数f（x）图象的一条对称轴； ③函数f（x）的最小正周期是π； ④将函数f（x）的图象向右平移 π 6 个单位后，对应的函数是偶函数．其中所有正确结论的序号是______．
6 臭氧的化学式是O 3下列对臭氧的说法不正确的是（） A．它由氧元素组成 B．它与氧分子互为同分异构体 C．它是氧的同素异形体 D．一个臭氧分子由3个氧原子构成
7 非洲的热带雨林气候主要分布在 A.东非高原 B.撒哈拉地区 C.南非高原 D.刚果盆地
8 非洲最主要的粮食作物是 A.咖啡、可可 B.花生、油棕 C.玉米 D.小麦、水稻
9 有反应2FeS0 4=Fe 20 3+S0 2↑+S0 3↑，将生成的混合气体通入BaCl 2溶液中生成的沉淀是 A．Ba(HS03)2 B．BaS03 C．BaS04 D．BaS03和BaS04
10 He’s already ridden the horse before ,______? A.is he B.isn’t he C.has he D.hasn’t he