第三部分：閱讀理解（共20題；每小題1.5分，滿分30分）
閱讀下列短文，從每題所給的四個(gè)選項(xiàng)中，選出最佳選項(xiàng)。
From age eight to eleven, I attended a small school in Bath, England. It was a small school of four classes with about twenty-five children in each class according to age. For the most part, one teacher had to teach all subjects to the children in the class. However, sometimes the headmaster, Mr. Ronald Broaches, would come in and spend an hour or so, teaching some subjects in which he was especially interested. He was a large man with a very happy nature. He had a sense of humor and would delight in telling the children small stories that would make us laugh. He was a very fair man and had a great influence on many of the children. In my own case, I found that he took great interest in me and he quickly found that I enjoyed puzzles. He would often stop me as I was going to class and take a piece of paper out of his pocket, often with a puzzle already on it. The puzzles were usually mathematical or logical. As time went on, they slowly got more difficult, but I loved them. Not only that, they made me interested in math and problem solving that stays with me to this day. They also served to show me that intellectual activity was rewarding when the correct answers were found, but perhaps more importantly it was great fun. To this day, I can remember Mr. Broaches’ cheerful cry of “Well done!” whenever I got a problem right. The simple communication with a man whom I loved greatly has had a deep influence on my life. I shall forever be thankful that our paths crossed. Mr. Broaches died just two weeks after I had won the 1993 Nobel Prize in Physiology or Medicine. Unluckily, I had no chance to speak to him before he died. I learnt later that he had heard of my success and I will always hope that he knew the deep influence he had made on my life.
56. There were ________ children in each class when Richard was in     the school in Bath, England.
A. 4          B. 8        C. 11              D. 25
57. From the text, we can learn that ___________.
A. the puzzles made the students laugh
B. the students were afraid of the headmaster
C. the puzzles made Richard enjoy math
D. the headmaster never taught in the school
58. The writer felt sorry because __________.
A. Mr. Broaches had passed away before he won the Nobel Prize
B. he didn’t express his thanks before Mr. Broaches died
C. he couldn’t find Mr. Broaches after he grew up
D. Mr. Broaches didn’t know his success
59. What is the best title（標(biāo)題）for the text ?
A. The Story of Mr. Broaches.
B. The Story of Richard J. Roberts.
C. My Early School Life.
D. An Important Teacher in My Life.

【小題1】D
【小題2】C
【小題3】B
【小題4】D解析:
         
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科目：初中物理 來(lái)源： 題型：閱讀理解

閱讀下面的現(xiàn)代文，完成文后各題
與植物相處
李漢榮
①不管如何，與人相處多了也會(huì)有煩的時(shí)候。即使孔夫子在世，天天接受他老人家的教導(dǎo)，恐怕有時(shí)候也想請(qǐng)假兩天在家里閉門思過(guò)，享受獨(dú)處的寧?kù)o。即使李白在月光下復(fù)活，與他三五天喝醉一次是可以的，甚至是“不亦快哉”的，但如果日日狂飲，夜夜醉倒，不僅詩(shī)寫不出來(lái)，還會(huì)喝垮了身體�！笆ト恕焙汀霸�(shī)仙”尚且如此，何況世上并非都是你喜歡和熱愛的人，產(chǎn)生“煩”甚至更不好的情緒就難免了。
②寵物大約就是由此“寵”起來(lái)的，人們養(yǎng)貓、養(yǎng)狗、養(yǎng)鳥，養(yǎng)一些可愛溫訓(xùn)的動(dòng)物，動(dòng)機(jī)之一恐怕就是想適度地拉開與“同類”的距離，而在與“異類”的相處中感受一種無(wú)憂的情趣。與這些動(dòng)物相處，人可以回復(fù)到一種簡(jiǎn)單的心境，不必戒備和算計(jì)，也不必那么多的禮節(jié)，更不用點(diǎn)頭哈腰獻(xiàn)媚討好。這一切都免了，動(dòng)物不欣賞人類的文化，你只要喜歡它，它就給你回報(bào)：貓就偎在你的懷里，狗就向你撒嬌，鳥就向你唱歌。在簡(jiǎn)單、純潔的動(dòng)物面前，人也變得簡(jiǎn)單、純潔了，人就有了從容、寧?kù)o、無(wú)邪的心境，領(lǐng)略生命與生命交流的喜悅。
③但是人能與之相處的動(dòng)物的種類還是太少了，寵物是人精心選擇知馴化了的。人不能和狼相處，麻雀好像壓根兒不想與人類建立什么親近的關(guān)系，它們只喜歡給人類制造一些小麻煩。人更無(wú)法考慮與虎、豹子等兇猛的動(dòng)物相處，只能在動(dòng)物園里隔著鐵柵欄遠(yuǎn)遠(yuǎn)地欣賞它們的英姿。
④這樣，我們就格外思念大自然中的植物了。于是我來(lái)到植物們面前，它們是我的老師和朋友。
⑤這泛綠的青草可是從白居易的詩(shī)里生長(zhǎng)出來(lái)?蒙蒙細(xì)雨里，我?guī)撞骄妥哌M(jìn)了唐朝，隱約間仿佛看見了李商隱、王維們的背影，青草綠了他們的詩(shī)，綠了古中國(guó)的記憶。我看見了車前草，還是在《詩(shī)經(jīng)》里那么優(yōu)美地?fù)u曳著。狗尾巴草，那么天真地守在路邊，誰(shuí)家的狗丟了尾巴?遍地好看的狗尾巴，令千年萬(wàn)載的孩子們想找到那一定很好看的狗。三葉草，三片葉子指著三個(gè)方向，哪一個(gè)方向都通向蝴蝶的翅膀。趁我伏在泉邊喝水的時(shí)候，野百合悄悄地開了。潔白的手在風(fēng)里打著手勢(shì)，似乎謝絕與我相握，它嫌我的手太粗糙，嫌我的氣息太渾濁?太陽(yáng)花開了，這么燦爛的笑，我看見太陽(yáng)的顏色了，我比天文學(xué)家看得清楚，我不用到天上去看，太陽(yáng)的親生女兒全都告訴我了。
⑥茉莉、菊、梔子、玫瑰……輕輕地叫一聲它們的名字，就感到靈魂里生出溫柔、芬芳的氣息。是的，許多植物的名字太美了，美得你不忍心大聲呼叫它們。含著感情輕輕叫一聲玉蘭，那潔白如玉的花瓣會(huì)灑落你一身，你便感到這個(gè)春天的愛情又純潔又慷慨。靜靜地守在曇花旁邊，不要為天上的星月繚亂了視線，注視它吧，它漫長(zhǎng)的一生里只有這一個(gè)燦爛的瞬間。竹子正直地生長(zhǎng)著；芭蕉粗中有細(xì)，準(zhǔn)確地捕捉了風(fēng)的動(dòng)靜；仙人掌握著滿把孤獨(dú)，又用一手的刺拒絕輕薄的同情；一不留神，青藤就爬上了絕壁；野草莓想走遍廈天，卻被一條蠻不講理的溪水擋住了去路。我也被擋住了去路，于是就躺下來(lái)。一覺(jué)醒來(lái)，野草莓包圍了我，多虧不遠(yuǎn)處松林里那五顏六色的蘑菇向我不停地遞眼神，讓我看見一條通向遠(yuǎn)方的幽徑，否則，我怎么能走出這溫柔而芬芳的圍困?。
⑦有一小塊自己的莊稼地多好啊!看一會(huì)兒書種一會(huì)兒莊稼，寫一首詩(shī)侍弄一會(huì)兒花草。書里的思想抖落進(jìn)泥土，會(huì)開出奇異的花；泥土的氣息漫進(jìn)詩(shī)，詩(shī)會(huì)有終年不散的充沛的春墑。看青翠挺拔的玉米怎樣抱起自己心愛的娃娃，看聰明的辣椒怎樣在寒冷的土里找到一把一把的火，看豆莢躺在小床上如何構(gòu)思，看韭菜排列得那么整齊，像杜甫的五律……
⑧與植物呆在一起，人會(huì)變得誠(chéng)實(shí)、善良、溫柔并懂得知恩必報(bào)。世上沒(méi)有虛偽的植物，沒(méi)有邪惡的植物，沒(méi)有懶惰的植物。植物開花不是為了炫耀自己，它是為自己開的，無(wú)意中把你的眼睛照亮了。植物終生都在工作，即使埋在土里，它也不會(huì)忘記自己的責(zé)任。你無(wú)意灑落一滴水，植物來(lái)年會(huì)回報(bào)你一朵花。沒(méi)有誰(shuí)告訴它生活的哲學(xué)，植物的哲學(xué)導(dǎo)師是深沉的土地。
【小題1】文章標(biāo)題是“與植物相處”，可作者在第②③段寫與寵物相處，請(qǐng)說(shuō)說(shuō)這兩段在文中的作用。(4分)
【小題2】第⑤段中“青草綠了他們的詩(shī)，綠了古中國(guó)的記憶”一句有什么含義?請(qǐng)作簡(jiǎn)要闡釋。(4分)
【小題3】第⑥段劃線部分在表達(dá)上有什么特色?請(qǐng)簡(jiǎn)要分析。(6分)
【小題4】作者說(shuō)“不管如何，與人相處多了也會(huì)有煩的時(shí)候”，請(qǐng)結(jié)合對(duì)文中植物“生活哲學(xué)”的理解，談?wù)勗鯓硬拍芨玫嘏c人相處?(份)

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科目：初中物理 來(lái)源： 題型：閱讀理解



第三部分：閱讀理解（共20題；每小題1.5分，滿分30分）
閱讀下列短文，從每題所給的四個(gè)選項(xiàng)中，選出最佳選項(xiàng)。
From age eight to eleven, I attended a small school in Bath, England. It was a small school of four classes with about twenty-five children in each class according to age. For the most part, one teacher had to teach all subjects to the children in the class. However, sometimes the headmaster, Mr. Ronald Broaches, would come in and spend an hour or so, teaching some subjects in which he was especially interested. He was a large man with a very happy nature. He had a sense of humor and would delight in telling the children small stories that would make us laugh. He was a very fair man and had a great influence on many of the children. In my own case, I found that he took great interest in me and he quickly found that I enjoyed puzzles. He would often stop me as I was going to class and take a piece of paper out of his pocket, often with a puzzle already on it. The puzzles were usually mathematical or logical. As time went on, they slowly got more difficult, but I loved them. Not only that, they made me interested in math and problem solving that stays with me to this day. They also served to show me that intellectual activity was rewarding when the correct answers were found, but perhaps more importantly it was great fun. To this day, I can remember Mr. Broaches’ cheerful cry of “Well done!” whenever I got a problem right. The simple communication with a man whom I loved greatly has had a deep influence on my life. I shall forever be thankful that our paths crossed. Mr. Broaches died just two weeks after I had won the 1993 Nobel Prize in Physiology or Medicine. Unluckily, I had no chance to speak to him before he died. I learnt later that he had heard of my success and I will always hope that he knew the deep influence he had made on my life.
56. There were ________ children in each class when Richard was in     the school in Bath, England.
A. 4          B. 8        C. 11              D. 25
57. From the text, we can learn that ___________.
A. the puzzles made the students laugh
B. the students were afraid of the headmaster
C. the puzzles made Richard enjoy math
D. the headmaster never taught in the school
58. The writer felt sorry because __________.
A. Mr. Broaches had passed away before he won the Nobel Prize
B. he didn’t express his thanks before Mr. Broaches died
C. he couldn’t find Mr. Broaches after he grew up
D. Mr. Broaches didn’t know his success
59. What is the best title（標(biāo)題）for the text ?
A. The Story of Mr. Broaches.
B. The Story of Richard J. Roberts.
C. My Early School Life.
D. An Important Teacher in My Life.

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科目：初中物理 來(lái)源： 題型：閱讀理解



第三部分：閱讀理解（共20題；每小題1.5分，滿分30分）
閱讀下列短文，從每題所給的四個(gè)選項(xiàng)中，選出最佳選項(xiàng)。
From age eight to eleven, I attended a small school in Bath, England. It was a small school of four classes with about twenty-five children in each class according to age. For the most part, one teacher had to teach all subjects to the children in the class. However, sometimes the headmaster, Mr. Ronald Broaches, would come in and spend an hour or so, teaching some subjects in which he was especially interested. He was a large man with a very happy nature. He had a sense of humor and would delight in telling the children small stories that would make us laugh. He was a very fair man and had a great influence on many of the children. In my own case, I found that he took great interest in me and he quickly found that I enjoyed puzzles. He would often stop me as I was going to class and take a piece of paper out of his pocket, often with a puzzle already on it. The puzzles were usually mathematical or logical. As time went on, they slowly got more difficult, but I loved them. Not only that, they made me interested in math and problem solving that stays with me to this day. They also served to show me that intellectual activity was rewarding when the correct answers were found, but perhaps more importantly it was great fun. To this day, I can remember Mr. Broaches’ cheerful cry of “Well done!” whenever I got a problem right. The simple communication with a man whom I loved greatly has had a deep influence on my life. I shall forever be thankful that our paths crossed. Mr. Broaches died just two weeks after I had won the 1993 Nobel Prize in Physiology or Medicine. Unluckily, I had no chance to speak to him before he died. I learnt later that he had heard of my success and I will always hope that he knew the deep influence he had made on my life.
56. There were ________ children in each class when Richard was in     the school in Bath, England.
A. 4          B. 8        C. 11              D. 25
57. From the text, we can learn that ___________.
A. the puzzles made the students laugh
B. the students were afraid of the headmaster
C. the puzzles made Richard enjoy math
D. the headmaster never taught in the school
58. The writer felt sorry because __________.
A. Mr. Broaches had passed away before he won the Nobel Prize
B. he didn’t express his thanks before Mr. Broaches died
C. he couldn’t find Mr. Broaches after he grew up
D. Mr. Broaches didn’t know his success
59. What is the best title（標(biāo)題）for the text ?
A. The Story of Mr. Broaches.
B. The Story of Richard J. Roberts.
C. My Early School Life.
D. An Important Teacher in My Life.

查看答案和解析>>

科目：初中物理 來(lái)源： 題型：閱讀理解

摘要：本文分析了如何挖掘物理題中隱含條件的途徑和方法。并對(duì)物理學(xué)試題題型進(jìn)行歸類、例舉和解析。學(xué)生要解好物理題，必須要有扎實(shí)的物理知識(shí)和相關(guān)學(xué)科的知識(shí)，綜合分析和解決問(wèn)題的能力。因此，在物理教學(xué)過(guò)程中要注重提高學(xué)生的解題能力，加強(qiáng)對(duì)解題方法的教學(xué)。

關(guān)鍵詞：隱含條件　物理學(xué)　解題能力

學(xué)習(xí)在解物理習(xí)題時(shí)，經(jīng)常會(huì)遇到這種情況，有些解題的必要條件，題中并為明確給出，而是隱含在字里行間。充分挖掘隱含條件，明確題目要求，采用合適方法，選擇正確答案，是解好這類題的關(guān)鍵。本文就如何挖掘試題中的隱含條件，提高解題能力作一例析。

一、從關(guān)鍵詞中挖掘隱含條件

在物理題中，常見的關(guān)鍵用語(yǔ)有：表現(xiàn)為極值條件的用語(yǔ)，如“最大”、“最小”、“至少”、“剛好”等，它們均隱含著某些物理量可取特殊值；表現(xiàn)為理想化模型的用語(yǔ)，如“理想滑輪”、“輕質(zhì)杠桿”、“光滑水平面”等，扣住關(guān)鍵用語(yǔ)，挖掘隱含條件，能使解題靈感頓生。

例1 一個(gè)物體在平衡力的作用下，在光滑水平面上做勻速直線運(yùn)動(dòng)，當(dāng)這對(duì)平衡力突然消失，則物體將（�。�

A．立刻停止運(yùn)動(dòng)

B．運(yùn)動(dòng)速度越來(lái)越快

C．速度減慢，最后停止

D．仍作勻速直線運(yùn)動(dòng)

解析：題中“光滑水平面”為關(guān)鍵詞。光滑水平面意味著物體不受摩擦力的作用。題目中的物體待平衡力消失后，將不再受力的作用，因此仍要保持勻速直線運(yùn)動(dòng)（牛頓第一定律）。

答案：D

二、從物理學(xué)常識(shí)中找隱含條件

有些題目幾乎沒(méi)有條件，但仔細(xì)研究就會(huì)發(fā)現(xiàn)條件其實(shí)全部隱含于物理常識(shí)中，這就要求學(xué)生根據(jù)題意進(jìn)行發(fā)散性思維，努力挖掘相關(guān)知識(shí)，在條件不足的情況下，根據(jù)常識(shí)假設(shè)適當(dāng)?shù)臈l件和數(shù)據(jù)以彌補(bǔ)題中明確給出的已知條件的不足。

例2 一個(gè)中學(xué)生對(duì)地面的壓強(qiáng)大約是（�。�

A．10Pa   B．100Pa   C．1000Pa     D．10000Pa

解析：此題隱含條件有兩個(gè)，一是中學(xué)生的體重約為50kg，二是中學(xué)生雙腳底面積約為5dm2，而這兩個(gè)條件都非常隱蔽，屬于物理學(xué)常識(shí)，只要明確了這兩點(diǎn)，不難得出正確答案D。

三、從物理學(xué)發(fā)展史中尋找隱含條件

這類試題一般涉及對(duì)物理學(xué)研究有貢獻(xiàn)的科學(xué)家、科研成果和歷史進(jìn)程等，增加了學(xué)生的愛國(guó)情感，有利于培養(yǎng)學(xué)生的高尚情操，激起學(xué)生學(xué)習(xí)生物學(xué)知識(shí)的遠(yuǎn)大理想。

例3 發(fā)電機(jī)和電動(dòng)機(jī)的發(fā)明使人類步入電氣化時(shí)代，制造發(fā)電機(jī)的主要依據(jù)是電磁感應(yīng)現(xiàn)象，首先發(fā)現(xiàn)電磁感應(yīng)現(xiàn)象的是（�。�

A．愛因斯坦

B．帕斯卡

C．奧斯特

D．法拉第

解析：知道這些科學(xué)家的研究成果和對(duì)社會(huì)的巨大貢獻(xiàn)，很快就能準(zhǔn)確地選出正確答案D。

四、從物理現(xiàn)象的出現(xiàn)條件中尋找隱含條件

一定的物理現(xiàn)象的出現(xiàn)，是以具備一定的條件為前提的，當(dāng)知道什么條件具備時(shí)可出現(xiàn)什么現(xiàn)象后，一旦題目給出某種現(xiàn)象，馬上可以找出相應(yīng)的隱含條件。

例4 我國(guó)“遠(yuǎn)望號(hào)”衛(wèi)星測(cè)控船從江陰出發(fā)執(zhí)行任務(wù)，由長(zhǎng)江進(jìn)入海洋。下列有關(guān)測(cè)控船所受浮力的說(shuō)法正確的是（�。�

A．由于海水的密度大，所以船在海洋力受到的浮力大

B．由于船排開海水的體積小，所以它在海洋里受到的浮力小

C．由于船排開的海水的體積大，所以它在海洋力受到的浮力大

D．由于船始終漂浮在水面上，所以它受到的浮力不變

解析：“一個(gè)物體漂浮在液面上……”，出現(xiàn)這種現(xiàn)象的條件是物體所受浮力等于物重，所以隱含條件是物體受到的浮力等于重力。

答案：D

例5 放在水平常木板上重10N的木塊，受到水平向右，大小為5N的拉力作用，沿水平方向做勻速直線運(yùn)動(dòng)，這時(shí)木板水平方向受的合力為_______N。當(dāng)拉力增大到8N時(shí)，木塊受到的合力為_______N。

解析：“一個(gè)物體勻速運(yùn)動(dòng)……”要出現(xiàn)這種現(xiàn)象，前提條件是物體必須不受力或受平衡力作用，所以隱含條件為：物體不受力或受平衡力作用。

答案：0；3

五、從物理概念、物理原理中尋找隱含條件

有些物理學(xué)問(wèn)題、現(xiàn)象、判斷等條件隱含于相關(guān)的概念和原理中，或是命題時(shí)有意混淆概念，偷換概念，要求學(xué)生對(duì)概念掌握準(zhǔn)確，理解要透徹。

例6 晴天，幾位大學(xué)生在森林中迷路了，下面四種利用風(fēng)向引導(dǎo)他們走出森林的說(shuō)法中，正確的是_______（圖中虛線為空氣流動(dòng)形成風(fēng)的路徑示意圖）

A．森林吸熱，溫度升高慢，空氣溫度低、密度大，地面空氣從森林流向外界，應(yīng)順風(fēng)走

B．土地吸熱，溫度升高快，空氣溫度高、密度小，地面空氣從外界流向森林，應(yīng)順風(fēng)走

C．森林吸熱，溫度升高慢，空氣溫度低、密度大，地面空氣從森林流向外界，應(yīng)迎風(fēng)走

D．土地吸熱，溫度升高快，空氣溫度高、密度小，地面空氣從外界流向森林，應(yīng)迎風(fēng)走

解析：本題中隱含了比熱容的概念。物體的比熱容越大，吸收熱量后溫度變化越小。

土地的比熱容大，吸熱后溫度升高較快，空氣溫度高。熱空氣因密度小而向上升，地面空氣從森林流向外界，應(yīng)順風(fēng)走。

答案：A

六、數(shù)學(xué)關(guān)系之中尋找隱含條件

正確的示意圖不僅能幫助我們理解題意、啟發(fā)思路，而且還能通過(guò)數(shù)學(xué)關(guān)系找出題中的隱含條件。這種方法不僅在幾何光學(xué)中有較多的應(yīng)用，而且在其它物理問(wèn)題中也經(jīng)常應(yīng)用。

例7 有一均勻正方體對(duì)水平地面的壓力是F，壓強(qiáng)是P，如下圖所示。若切去陰影部分，則剩余部分對(duì)地面的壓力是原來(lái)的_______倍，壓強(qiáng)是原來(lái)的_______倍。

解析：該題的條件隱含在數(shù)學(xué)關(guān)系之中，解題的關(guān)鍵要建立物理模型的空間想象力。切去部分的正方體邊長(zhǎng)為a/2，體積為V/8。切去陰影部分后，其質(zhì)量為7/8m，底部受力面積為3/4S，剩余部分壓強(qiáng)為P’＝m/S＝7/6P，壓力為F’＝Ps＝7/8F。

答案：7/8；7/6

七、從圖形、圖表與曲線關(guān)系中尋找隱含條件

圖示是貯存和傳遞科學(xué)文化知識(shí)比較便捷的一條途徑，它能夠高度濃縮物理學(xué)的基本概念及原理，使之更加形象、直觀。試題圖文并茂，生動(dòng)活潑，但圖表曲線中隱含了相當(dāng)多的沒(méi)有敘述和未提及的條件，解題時(shí)結(jié)合題設(shè)條件分析圖形，從圖形中挖掘隱含條件，才能正確作答，較好地培養(yǎng)學(xué)生的觀察和分析問(wèn)題的能力。

例8 在如圖所示的各圖中，關(guān)于磁場(chǎng)的描述和小磁針表示正確的是（�。�

解析：這是一道集概念、實(shí)驗(yàn)和理論于一體的圖形選擇題，要求學(xué)生明確磁場(chǎng)的概念、磁場(chǎng)方向及磁場(chǎng)方向的規(guī)定等情況，這樣才可選出正確答案為B。

八、從實(shí)驗(yàn)的器材、操作過(guò)程或結(jié)果中尋找隱含條件

在理論試題中，也有相當(dāng)多的題干條件看似不足，其實(shí)隱含在實(shí)驗(yàn)器材、操作步驟和實(shí)驗(yàn)結(jié)果之中，要求學(xué)生根據(jù)已有知識(shí)，挖掘這些隱含條件，從而得出正確答案，這有利于考查學(xué)生的實(shí)驗(yàn)操作技能，有利于培養(yǎng)學(xué)生的創(chuàng)新精神和實(shí)踐能力。

例9 如圖所示電路，圖中1、2、3表示電流表或電壓表，請(qǐng)?zhí)钌细鞅黼娐贩?hào)．并標(biāo)出正、負(fù)接線柱的位置。

解析：判斷電表的類型，需了解器材的使用規(guī)則。電流表要串聯(lián)接入電路，電壓表要并聯(lián)接入電路。判斷時(shí)，可假設(shè)將改表處斷開，凡對(duì)電路結(jié)構(gòu)有影響的是電流表，沒(méi)有影響的是電壓表。答案如上圖。

九、選擇合適的方法

確定解題思路，根據(jù)題型特點(diǎn)，充分理解題意。采用合適方法，能很好地提高解題能力，常用的物理方法有控制變量法、等效法、轉(zhuǎn)換法、數(shù)據(jù)歸納法等。

例10 下表列出由實(shí)驗(yàn)測(cè)定的幾種物質(zhì)的比熱容。認(rèn)真閱讀，你一定會(huì)有所發(fā)現(xiàn)，請(qǐng)?zhí)畛鋈我馊龡l：

水4． 2×103

冰 2．1×103

鋁 0．88×103

鋼鐵 0．46×103

酒精 2．4×103

蓖麻油1．8×103

干泥土0．8×103

水銀0．14×103

煤油2．1×103

砂石0．92×103

銅0．39×103

鉛0．13×103

（1）________________________________________；

（2）________________________________________；

（3）________________________________________。

解析：給表找規(guī)律時(shí)一般采用比較分析，綜合分析的方法，即可找一般規(guī)律如某種變大或變小的趨勢(shì)，共性等，也可找特殊規(guī)律。此表中12種物質(zhì)除煤油和冰比熱相同外，其他不同。說(shuō)明不同物質(zhì)得比熱一般不同，這是共性。但冰和煤油不同物質(zhì)比熱相同這是特殊性質(zhì)。水、冰同種物質(zhì)，狀態(tài)不同，比熱容也不同。且可將物質(zhì)分為金屬、非金屬進(jìn)行比較。還可找比熱容最大的、最小的。

例11 用實(shí)驗(yàn)研究決定電阻大小的因素，供選擇的導(dǎo)體規(guī)格如下表:

材料

編號(hào)

長(zhǎng)度（m）

橫截面積（mm）2

鎳鉻合金

①

1

0．5

②

1．5

0．5

錳銅

③

1

0．5

④

1．5

1

①要比較電阻與長(zhǎng)度的關(guān)系應(yīng)選擇導(dǎo)線：_______________________；

②要比較電阻與橫截面積的關(guān)系應(yīng)選擇導(dǎo)線：_______________________；

③要比較電阻與材料的關(guān)系應(yīng)選擇導(dǎo)線：_______________________。

解析：本題中導(dǎo)體的電阻與導(dǎo)體的長(zhǎng)度、材料、橫截面積三個(gè)物理量有關(guān)，要探究它們之間的關(guān)系，要采用“控制變量法”。要驗(yàn)證猜想一，就要取不同的長(zhǎng)度，相同材料和橫截面積的導(dǎo)線，所以應(yīng)選序號(hào)1、2，同理可選出另兩個(gè)猜想的序號(hào)。

答案：（1）1、2；（2）3、4；（3）1、3

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