日日人人_亚洲美女在线视频_av手机在线播放_国产大片aaa_欧美中文日韩_午夜理伦三级

精英家教網 > 初中地理 > 題目詳情

【題目】下列關于聲音的產生和傳播說法正確的是( )

A.物體不振動也可以發出聲音

B.空氣不能充當傳播聲音的介質

C.聲音在真空中的傳播速度為340m/s

D.音調與聲源物體振動的快慢有關

【答案】D

【解析】

試題分析:聲音是發聲體振動產生的,一切發聲的物體都在振動;

聲音的傳播需要介質,它既可以在氣體中傳播,也可以在固體和液體中傳播;

聲音的高低叫音調,音調與發聲體振動的快慢有關,振動越快音調越高.

解:

A、聲音是發聲體振動產生的,物體不振動不能發出聲音,此選項錯誤;

B、固體、液體和氣體都可以作為聲音傳播的介質,聲音可以在空氣中傳播,此選項錯誤;

C、聲音傳播需要介質,真空不能傳聲,此選項錯誤;

D、音調與聲源振動的快慢有關,振動越快音調越高,此選項正確.

故選D.

練習冊系列答案
相關習題

科目:初中地理 來源: 題型:

【題目】A special day in the United States is Thanksgiving Day. It is always on the fourth Thursday of November. Usually, family members and friends get together for a big dinner. People sometimes drive their cars a long way for a family reunion(團聚). Many people also take Friday off and make it a long weekend holiday, because most Americans do not work on Saturdays or Sundays. Thanksgiving Day began in 1621, the second year after the first English settlers(定居者) reached the new world. They did not have enough food. But the American Indians helped the white men and taught them how to farm.

In the autumn after the English settlers came to America, they had a good harvest(豐收). They were so pleased. They decided to invite their Indian friends to dinner in order to (為了) thank them for their help. In terms of a family reunion, Thanksgiving Day is even more important than Christmas Day or New Year's Day to most Americans.

1If November 1st is Monday, when is Thanksgiving Day?

A. On November 4. B. On November 18.

C. On November 25. D. On November 2.

2In the passage the American Indians were very ________.

A. brave B. foolish C. kind D. clever

3When the first English settlers reached America they ______.

A. lived happily

B. had a difficult time

C. taught the American Indians how to farm

D. brought the American Indians food

4Why did the English settlers invite the American Indians to dinner?

A. To thank them for their help.

B. To have a long holiday.

C. To teach them how to farm.

D. To drive a long way for a family reunion.

5We can guess there are more family reunions ________ in America.

A. on Thanksgiving Day than on Christmas Day

B. on Christmas Day than on Thanksgiving Day

C. on New Year's Day than on Thanksgiving Day

D. on New Year's Day than on Christmas Day

查看答案和解析>>

科目:初中地理 來源: 題型:

【題目】Can we bring food to the cinema?

I ________ so. If you do that, they wont let you in.

A. think B. dont think C. hope D. dont hope

查看答案和解析>>

科目:初中地理 來源: 題型:

【題目】

until

glad

when

kind

invite

surprise

catch

guest

Having a surprise party is very popular,Most peo1ple are 1 to have a surprise party for their family and friends. Do you know what a surprise party is like? Let me give you an example.

It was half past six in the evening.Bob 2 his father Mr. Green to his bedroom to play chess.3 Mr.Green opened the door, he found the room was dark.Suddenly (突然) a lion 4 him.He was a little afraid.Then the light was on. He found the lion was Bob! Behind Bob, Mr.Green saw his wife and some 5.All of them said to Mr.Green, “Suprise!?” Mr.Green was confused(迷惑的). He didn't know what it was 6all of them said“Happy birthday”to him.

There are different 70f surprise parties. But a successful surprise party always makes pcople feel 8and happy.

查看答案和解析>>

科目:初中地理 來源: 題型:

【題目】Part III: 句型:

1世界上有多少種鶴?________________________________________________

2它是適合一些珍稀鳥類生活的完美地方。

_________________________________________________________________

3世界上的鶴所剩不多。_____________________________________________

4為了騰出更多空間用作農田和建筑,有一些人想要使濕地更小。

_________________________________________________________________

5這將導致野生生物的空間越來越小。

_________________________________________________________________

6此外,漁民們一直在那里捕魚。

_________________________________________________________________

7如今中國政府已經制定法律阻止在扎龍的所有這些做法。

_________________________________________________________________

8許多游客去扎龍觀鳥。____________________________________________

9我們需要更多的人來數鳥和描述鳥。

_________________________________________________________________

10我們希望這將會幫助人們理解濕地的重要性

_________________________________________________________________

查看答案和解析>>

科目:初中地理 來源: 題型:

【題目】平面鏡成像特點是:成的像是 像,像與物體的大小 ,像和物體到平面鏡的距離

查看答案和解析>>

科目:初中地理 來源: 題型:

【題目】現實生活中有些酒店時常設置最低消費,這樣做不但侵害了消費者的合法權益,還可能造成鋪張浪費。設置最低消費侵害了消費者的______________。( )

A. 自主選擇權、公平交易權 B. 安全權、知情權

C. 自主選擇權、依法求償權 D. 公平交易權、知情權

查看答案和解析>>

科目:初中地理 來源: 題型:

【題目】5分一般違法與犯罪的區別

一般違法

犯罪

社會危害性

違法性

應當受處罰性

承擔刑法以外的法律責任

查看答案和解析>>

科目:初中地理 來源: 題型:

【題目】黨的十八大提出要更加注重強調社會公平。下列選項中,體現了社會公平的是

A.堅持教育優先發展 B.規范個人收入分配

C.開拓網絡交往空間 D.注重個人品德修養

查看答案和解析>>

同步練習冊答案
主站蜘蛛池模板: 欧美成人午夜 | 国产福利视频在线 | 成人在线观看网站 | 免费色视频 | 亚洲欧美在线视频 | 精品久久久久久久久久久久久久久久 | 日韩精品一区在线 | 黄色片www | 日韩高清不卡 | 91最新网址 | 免费网站黄 | 91在线网| 日韩av综合网 | 国产成人91| 日日狠狠 | 免费观看一区二区 | 亚洲一级黄色片 | 国产一区二区自拍 | 日韩欧美小视频 | 欧美一级黄色片 | 欧美黄色一级 | 欧美综合激情 | 免费人成| 久久精品视 | 欧美激情网站 | 伊人黄色 | 在线国产小视频 | 亚洲一区视频 | 久久久久国产一区二区三区 | 精品一区二区三区免费看 | 特黄一级毛片 | 国产不卡在线观看 | 好色婷婷 | 国内外成人免费视频 | 国产一级视频在线观看 | 国产一级生活片 | 一区二区三区视频在线 | 青青久草 | 欧美专区第一页 | 一级黄色性生活片 | 免费黄色网址在线观看 |