题干

如图将正在发声的小电铃放在连通于抽气机的密闭玻璃罩内,则:

(1)在用抽气机把玻璃罩内的空气逐渐抽出的过程中,所听到的声音将会逐渐____ .

(2)此实验现象说明声音的传播需要____ .

 

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变小,介质

同类题2

阅读理解

    “How’s it going? ”  I ask the barista(服务生). “How’s your day been?”

    “Ah, not too busy. What are you up to?”

    “Not much. Just reading. ”

    This,small talk, is one of the key rituals(规矩)of American life. It has taken me only a decade to master.

    I immigrated to the United States in 2001, for college. I brought only my Indian experience in dealing with shopkeepers and tea sellers. In Delhi, where I grew up, when doing business, people don't ask each other how the other's day has been. They might not even smile. The customer doesn't tremble before complaining about how cold his food is. Each side believes the other will cheat him.

    “God, Mahajan, you’re so rude to waiters!” Tom, an American friend, said, laughing, after he watched me ordering food at a restaurant, in the West Village, years ago. Considering myself a mild and friendly person, I was surprised. Tom always asked servers how they were doing or praised their shirts or made jokes about the menu. At that time, this seemed dishonest to me. Did he really like what they were wearing?

    American life is based on a principle that we like one another but won’t violate one another’s privacies. This makes it a land of small talk. Two people greet each other happily, with friendliness, but might know each other for years before asking basic questions about each other’s backgrounds. The opposite is true of Indians. At least three people I’ve sat next to on planes to and from India have asked me, within minutes, how much I earn as a writer (only to turn away in disappointment when I tell them).

    Living in Brooklyn and then in Austin, Texas. I made coffee shops the places of my movements. Meeting the same baristas day after day produced context, and I got practice. I was beginning to fit in. It felt good and didn’t seem fake anymore.

同类题4

阅读下面记叙文,完成各题。

纯真年代里的纯真人情

       ①1978年5月,中央音乐学院和上海音乐学院在上海联合招生。我从家乡来到上海参加考试。上海音乐学院我名落孙山,中央音乐学院音乐系的复试名单榜要再过好几天才公布。我决定先回泰兴老家去等。走之前,我嘱咐一位亲戚:“到了发榜日,请帮我到上海音乐学院去看榜,如果有我的名字,赶紧给我拍个电报,我好赶来复试。”

       ②嘱咐了亲戚,我总感觉到不够放心。但我在上海就这么一位亲戚,还能拜托谁?想来想去,我想到了在考场上刚刚认识两天的一个考友﹣﹣王次炤。

       ③我和次在考场一见如故,谈得很投机。从他看我的眼神就可以知道,这是一个值得信赖的朋友。于是,在匆匆离开上海之际,我委托他在看榜时看到我的名字,给我发个电报。

       ④我是多么希望自己能够获得复试资格并被录取啊!比我年长7岁的次炤兄,毫无疑问肯定比我更希望获得复试资格。而那年中央音乐学院音乐系在全国范围内只招录10人,考生之间竞争之惨烈是不言而喻的。

       ⑤复试名单发榜那天是我的生日。早晨起来,我就开始等电报,等到中午,电报还没有来。下午4点多,门外响起了决定命运的敲门声﹣﹣来自中央音乐学院的复试通知终于到了。但当天泰兴到上海的班车已经没有了,唯一能让我赶上次日早上8点钟复试的,是离家20多公里的长江边上一班到上海的小客轮。那班客轮五等舱的乘客,全是带着农渔产品到上海赶早市的江北农民。而我,美滋滋地与那些即将被上海人民吃掉的鸡鸭鱼蟹呆在一起,向着我的未来航行

       ⑥那天深夜,就在我和各种动物酣睡在一起的时候,另外一份通知我复试的电报到了泰兴家里!家里人接到这份作为喜讯的电报,却惊出一身冷汗:如果我只委托一个人,而这个人恰恰是发送这份深夜才到的电报的主儿,我的前途就毁了!那么晚才收到复试电报,除非我有直升机,否则,无论如何也不可能赶上次日早8点在上海音乐学院进行的复试。

       ⑦后怕之余,家人感到庆幸﹣﹣幸亏那第一份电报到得及时!庆幸之后,大家又感到纳闷:是谁选择这么晚的时间把复试消息告诉我呢?上海到泰兴的电报从发送到接收大概需要4个小时,半夜来的电报,发送的时间应当是傍晚七八点。故意这么晚才把消息传给我,这个人是谁?

       ⑧家里人显然不会认为发第二份电报的是我的亲戚。那么,肯定是那位受我委托的考生,故意拖延到晚上才发电报。这样,既可以轻松消除一个竞争对手,又不必背负爽约之名。于是家里人都嗟叹人心险恶。

       ⑨可是,大家的推测都错了!恰恰是王次炤﹣﹣这位当时和我还素昧平生,只是在激烈竞争的考场上萍水相逢的考友,看到复试榜上有我的名字后,在第一时间给我发来了复试的喜讯。而我的亲戚后来告诉我:他那天起来就没想到看榜,到了傍晚时分,他信步走到离家不远的发榜处,在那里看到了我的名字,于是立即给我发了电报,虽然当时已经是晚上七八点钟了。

       ⑩亲戚是个老人家,我不能责怪他。但我心里充满了对次  兄的感激!如果不是他第一时间给我发来电报,我的大学梦一定会梦断扬子江了。

       ⑩我说不清楚,次炤兄后来担任中央音乐学院院长,和他当年给我发电报之间有什么因果关系。但有一点是肯定的:好人有好报!一个人做点好事并不难,难的是为和自己毫无关系甚至还有利益冲突的陌生人做好事。这一切堪称纯真年代里纯真人情的典范。

(选自2013年6期《读者》作者:徐小平  有删改)