A: 4:3; B: 1:3; C: 3:1; D: 3:4. 查看更多

 

題目列表(包括答案和解析)

a、b、c是三根鎳鉻合金線,已知a、b長度相同,b較粗;a、c粗細(xì)相同,c較短.要求在溫度不變的條件下用實(shí)驗(yàn)的方法研究導(dǎo)體的電阻跟其長度和橫截面積的關(guān)系,按要求回答下列問題.
(1)按要求完成實(shí)驗(yàn),至少還需要的器材有
電流表
電流表
,開關(guān)一個(gè),電源一個(gè),導(dǎo)線若干.
(2)選
a
a
、
c
c
兩根合金絲(選填“a”、“b”或“c”),可研究電阻的大小與
長度
長度
的關(guān)系.
(3)選
a
a
、
b
b
兩根合金絲(選填“a”、“b”或“c”),可研究電阻的大小與
橫截面積
橫截面積
的關(guān)系.
(4)上述關(guān)系都是在
電壓
電壓
相同的條件下,通過比較
電流
電流
得出的.
(5)完成上述探究,采用的科學(xué)研究方法是
A
A

A.控制變量法    B.等量替換法    C.實(shí)驗(yàn)推理法    D.理想模型法.

查看答案和解析>>

 

(1).請找出上圖a中的兩處錯(cuò)誤之處:①______________________________;

                                ②______________________________。

(2).小明在用圖a方法稱量時(shí),把物體放在天平的右盤,砝碼放在天平的左盤,并向右移動(dòng)游碼后天平恢復(fù)了平衡,則該物體的質(zhì)量應(yīng)是         (    )

  A.砝碼數(shù)加游碼指的示數(shù)    B.砝碼數(shù)減游碼指的示數(shù)

  C.僅等于砝碼數(shù)           D.無法準(zhǔn)確讀出物體的質(zhì)量

(3).若小明改正錯(cuò)誤稱量后,用天平測量液體的質(zhì)量.當(dāng)天平平衡時(shí),放在右盤中的砝碼大小和游碼的位置如圖b中甲所示,則稱得燒杯和液體的質(zhì)量m為________g.

(4).用量筒測量液體的體積.將燒杯中的液體全部倒入量筒中,液面達(dá)到的位置如圖b中乙所示,則該液體的體積V為________mL.盡管體積測量方法正確,但大家在對實(shí)驗(yàn)過程及結(jié)果進(jìn)行評估時(shí),發(fā)現(xiàn)液體的體積測量值比它的實(shí)際值要________,如果按這種方案,測得的密度值__________。(兩空均選填“偏大”或“偏小”).

 

 

(5).他們對測量方法進(jìn)行修正后,測出了幾組實(shí)驗(yàn)數(shù)據(jù),并根據(jù)測量結(jié)果作出了“m-V”圖象,如下圖所示.由圖象可知該液體的密度為________kg/m3通過查表對照知該液體可能是________.

 

                        

一些物質(zhì)的密度

 

 

查看答案和解析>>

 

 (1).請找出上圖a中的兩處錯(cuò)誤之處:①______________________________;

                                ②______________________________。

(2).小明在用圖a方法稱量時(shí),把物體放在天平的右盤,砝碼放在天平的左盤,并向右移動(dòng)游碼后天平恢復(fù)了平衡,則該物體的質(zhì)量應(yīng)是         (    )

  A.砝碼數(shù)加游碼指的示數(shù)    B.砝碼數(shù)減游碼指的示數(shù)

  C.僅等于砝碼數(shù)            D.無法準(zhǔn)確讀出物體的質(zhì)量

(3).若小明改正錯(cuò)誤稱量后,用天平測量液體的質(zhì)量.當(dāng)天平平衡時(shí),放在右盤中的砝碼大小和游碼的位置如圖b中甲所示,則稱得燒杯和液體的質(zhì)量m為________g.

(4).用量筒測量液體的體積.將燒杯中的液體全部倒入量筒中,液面達(dá)到的位置如圖b中乙所示,則該液體的體積V為________mL.盡管體積測量方法正確,但大家在對實(shí)驗(yàn)過程及結(jié)果進(jìn)行評估時(shí),發(fā)現(xiàn)液體的體積測量值比它的實(shí)際值要________,如果按這種方案,測得的密度值__________。(兩空均選填“偏大”或“偏小”).

(5).他們對測量方法進(jìn)行修正后,測出了幾組實(shí)驗(yàn)數(shù)據(jù),并根據(jù)測量結(jié)果作出了“m-V”圖象,如下圖所示.由圖象可知該液體的密度為________kg/m3 通過查表對照知該液體可能是________.

 

 

 

 

 

 

 


                      

 

查看答案和解析>>


 (1).請找出上圖a中的兩處錯(cuò)誤之處:①______________________________;
②______________________________。
(2).小明在用圖a方法稱量時(shí),把物體放在天平的右盤,砝碼放在天平的左盤,并向右移動(dòng)游碼后天平恢復(fù)了平衡,則該物體的質(zhì)量應(yīng)是         (    )
A.砝碼數(shù)加游碼指的示數(shù)B.砝碼數(shù)減游碼指的示數(shù)
C.僅等于砝碼數(shù)D.無法準(zhǔn)確讀出物體的質(zhì)量
(3).若小明改正錯(cuò)誤稱量后,用天平測量液體的質(zhì)量.當(dāng)天平平衡時(shí),放在右盤中的砝碼大小和游碼的位置如圖b中甲所示,則稱得燒杯和液體的質(zhì)量m為________g.
(4).用量筒測量液體的體積.將燒杯中的液體全部倒入量筒中,液面達(dá)到的位置如圖b中乙所示,則該液體的體積V為________mL.盡管體積測量方法正確,但大家在對實(shí)驗(yàn)過程及結(jié)果進(jìn)行評估時(shí),發(fā)現(xiàn)液體的體積測量值比它的實(shí)際值要________,如果按這種方案,測得的密度值__________。(兩空均選填“偏大”或“偏小”).
(5).他們對測量方法進(jìn)行修正后,測出了幾組實(shí)驗(yàn)數(shù)據(jù),并根據(jù)測量結(jié)果作出了“m-V”圖象,如下圖所示.由圖象可知該液體的密度為________kg/m3 通過查表對照知該液體可能是________.
 

查看答案和解析>>

A metaphor is a poetic device that deals with comparison. It compares similar qualities of two dissimilar objects. With a simple metaphor, one object becomes the other: Love is a rose. Although this does not sound like a particularly rich image, a metaphor can communicate so much about a particular image that poets use them more than any other type of figurative language(修辭). The reason for this is that poets compose their poetry to express what they are experiencing emotionally at that moment. Consequently, what the poet imagines love to be may or may not be love we see it. Therefore, the poet’s job is to enable us to experience it, to feel it the same way as the poet does.
Let’s analyze this remarkably unsophisticated metaphor concerning love and the rose to see what it offers. Because the poet uses a comparison with a rose, first we must examine the characteristics of that flower. A rose is spectacular in its beauty; its petals(花瓣) are nicely soft, and its smell is pleasing. It’s possible to say that a rose is actually a feast to the senses of sight, touch, and smell. The rose’s appearance seems to border on(近似于)perfection, each petal seemingly symmetrical(對稱的) in form. Isn’t this the way one’s love should be? A loved one should be a delight to one’s senses and seem perfect. However, there is another dimension added to the comparison by using a rose. Roses have thorns(刺). The poet wants to convey the idea that roses can be tricky(機(jī)警的). So can love, the metaphor tells us. When one reaches out with absolute trust to touch the object of his or her affection, ouch, a thorn can cause great harm! “Be careful,” the metaphor warns: Love is a feast to the senses, but it can overwhelm us, and it can also hurt us and cause acute suffering. This is the poet’s perception of love--a warning. What is the point? Just this: It took almost 14 sentences to clarify what a simple metaphor communicates in only four words! That is the artistry and the joy of the simple metaphor.
【小題1】According to the passage, what is a metaphor?
A.A comparison between two different objects with similar features.
B.A contrast between two different things to create a vivid image.
C.A description of two similar objects in a poetic way.
D.A literary device specially employed in poetry writing.
【小題2】 The main idea of this passage is that         .
A.rose is a good image in poetryB.love is sweet and pleasing
C.metaphor is ambiguousD.metaphor is great poetic device
【小題3】 It can be inferred from the passage that a metaphor is        .
A.difficult to understandB.rich in meaningC.not precise enoughD.like a flower
【小題4】 As is meant by the author, thorns of a rose_________.
A.protect the rose from harmB.symbolize reduced love
C.a(chǎn)dd a new element to the image of loveD.represent objects of one’s affection
【小題5】 The meaning of the love-is–a-rose metaphor is that____________-
A.love is a true joyB.true love comes once in a lifetime
C.love does not last long D.love is both good and bad experiences

查看答案和解析>>


同步練習(xí)冊答案