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问题 实验题

跟凸透镜主光轴平行的光线经过透镜后会聚的情形如图甲所示．若将一烛焰放在此凸透镜左侧如图乙所示的位置，则在透镜的 _________ 侧（填：“左”或“右”）可以看到一个烛焰 _________ 立的、 _________ 的（填：“放大”、“缩小”或“等大”）实像．生活中 _________ 就是利用这一原理制成的．

答案

右；倒；放大；投影仪

听力题

根据汉语意思和英文首字母完成下列单词拼写，使句意完整正确。

56. The tower in the d           (远处) is hundreds of years old.

57. First o           (观察) the teacher do the experiment and then have a try by yourself.

58. We should r           (尊敬) them instead of looking down upon them.

59. It’s well-known that smoking is h           (有害的) to health.

60.He said the song r_________ (提醒) him of the happy days in the university.

61. He has a firm b           (信念) that he’ll win the speech contest.      

62. What will happen to you if you don’t  eat a  b________ （均衡的）diet ?

63. Would you please come in? P           (允许) me to lead the way, sir.

64. There are v           (各种各样的) kinds of theme parks all over the world.

65. The tramp in the film was loved for his optimism and determination to o          (克服) all difficulties.
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问答题

小明利用气球做了以下几个小实验：

（1）图甲所示，说明力可以使物体发生______．

（2）图乙中两只气球自由悬挂在空中，用粗吸管对准A点沿垂直于纸面方向用力吹气，可观察到两气球______（选填“分开”或“合拢”）．

（3）图丙中，用一个摩擦过的气球靠近水平面上静止的空易拉罐，发现空易拉罐向气球一侧滚动，这是因为______的原因．

（4）图丁所示是小明在活动课中制作的喷气“气球火箭”，现在把封口的夹子松开，气球将由静止开始向右运动．在此过程中，______能转化为机械能．

（5）一氢气球下系一重为G的物体P，在空中做匀速直线运动．如不计空气阻力和风力影响，物体P恰能沿MN方向（如图中箭头指向）斜线上升，图中OO′为竖直方向，则在图中气球和物体P所处的情况正确的是______
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