题目

如图所示，是小明“探究凸透镜成像规律”的实验。 （1） 如图甲，平行光正对凸透镜照射，光屏上出现一个最小最亮的光斑，则凸透镜的焦距f=cm； （2） 实验前应调节烛焰、凸透镜、光屏三者的中心在同一高度上。这样做的目的是。 （3） 当蜡烛与凸透镜的距离如图乙所示时，在光屏上可得到一个清晰的倒立、的实像，生活中利用这个规律制成的光学仪器是。 （4） 接着，换用凸度更大的透镜，发现光屏上的像由清晰变模完形填空The Smiths are taking a vacation next week. At first, they thought about   1    to Beijing. Because they went there three times, so there’s nothing  2 for them. This time, they want to go  3 .   4 are they going then? “I want to go to Jiuzhaigou,” said Tom. “But it’s quite  5  from here and we have only two 6 ,” Mary disagreed. “I think we should go somewhere near here.” And  7 they decided  8  to Qingdao. Qingdao is famous     9   its beautiful beaches.They are leaving  10 Friday evening and staying there   11  two days. On the first day, they are going to the  12  to see the dolphins(海豚). On the second day, they are going to the beach and    13   there. They are taking  14  on the beautiful beach. They are sure that they will  15  themselves in Qingdao.小题1:A．to goB．wentC．goingD．goes小题2:A．goodB．boringC．newD．old小题3:A．different somewhereB．different anywhereC．anywhere differentD．somewhere different小题4:A．WhatB．WhereC．WhenD．How小题5:A．behindB．longC．farD．near小题6:A．weeksB．monthsC．yearsD．days小题7:A．lastB．firstC．at firstD．at last小题8:A．to goB．goingC．goD．went小题9:A．toB．aboutC．forD．at小题10:A．inB．onC．atD．to小题11:A．forB．inC．atD．on小题12:A．zooB．shopC．townD．cinema小题13:A．going swimming　　　　　B．going skatingC．playing tennis　　　D．playing baseball小题14:A．lessons B．photosC．soccerD．movie小题15:A．likeB．enjoyC．enterD．study