A: 4:3; B: 1:3; C: 3:1; D: 3:4. 查看更多

 

题目列表(包括答案和解析)

a、b、c是三根镍铬合金线,已知a、b长度相同,b较粗;a、c粗细相同,c较短.要求在温度不变的条件下用实验的方法研究导体的电阻跟其长度和横截面积的关系,按要求回答下列问题.
(1)按要求完成实验,至少还需要的器材有
电流表
电流表
,开关一个,电源一个,导线若干.
(2)选
a
a
c
c
两根合金丝(选填“a”、“b”或“c”),可研究电阻的大小与
长度
长度
的关系.
(3)选
a
a
b
b
两根合金丝(选填“a”、“b”或“c”),可研究电阻的大小与
横截面积
横截面积
的关系.
(4)上述关系都是在
电压
电压
相同的条件下,通过比较
电流
电流
得出的.
(5)完成上述探究,采用的科学研究方法是
A
A

A.控制变量法    B.等量替换法    C.实验推理法    D.理想模型法.

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(1).请找出上图a中的两处错误之处:①______________________________;

                                ②______________________________。

(2).小明在用图a方法称量时,把物体放在天平的右盘,砝码放在天平的左盘,并向右移动游码后天平恢复了平衡,则该物体的质量应是         (    )

  A.砝码数加游码指的示数    B.砝码数减游码指的示数

  C.仅等于砝码数           D.无法准确读出物体的质量

(3).若小明改正错误称量后,用天平测量液体的质量.当天平平衡时,放在右盘中的砝码大小和游码的位置如图b中甲所示,则称得烧杯和液体的质量m为________g.

(4).用量筒测量液体的体积.将烧杯中的液体全部倒入量筒中,液面达到的位置如图b中乙所示,则该液体的体积V为________mL.尽管体积测量方法正确,但大家在对实验过程及结果进行评估时,发现液体的体积测量值比它的实际值要________,如果按这种方案,测得的密度值__________。(两空均选填“偏大”或“偏小”).

 

 

(5).他们对测量方法进行修正后,测出了几组实验数据,并根据测量结果作出了“m-V”图象,如下图所示.由图象可知该液体的密度为________kg/m3通过查表对照知该液体可能是________.

 

                        

一些物质的密度

 

 

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 (1).请找出上图a中的两处错误之处:①______________________________;

                                ②______________________________。

(2).小明在用图a方法称量时,把物体放在天平的右盘,砝码放在天平的左盘,并向右移动游码后天平恢复了平衡,则该物体的质量应是         (    )

  A.砝码数加游码指的示数    B.砝码数减游码指的示数

  C.仅等于砝码数            D.无法准确读出物体的质量

(3).若小明改正错误称量后,用天平测量液体的质量.当天平平衡时,放在右盘中的砝码大小和游码的位置如图b中甲所示,则称得烧杯和液体的质量m为________g.

(4).用量筒测量液体的体积.将烧杯中的液体全部倒入量筒中,液面达到的位置如图b中乙所示,则该液体的体积V为________mL.尽管体积测量方法正确,但大家在对实验过程及结果进行评估时,发现液体的体积测量值比它的实际值要________,如果按这种方案,测得的密度值__________。(两空均选填“偏大”或“偏小”).

(5).他们对测量方法进行修正后,测出了几组实验数据,并根据测量结果作出了“m-V”图象,如下图所示.由图象可知该液体的密度为________kg/m3 通过查表对照知该液体可能是________.

 

 

 

 

 

 

 


                      

 

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 (1).请找出上图a中的两处错误之处:①______________________________;
②______________________________。
(2).小明在用图a方法称量时,把物体放在天平的右盘,砝码放在天平的左盘,并向右移动游码后天平恢复了平衡,则该物体的质量应是         (    )
A.砝码数加游码指的示数B.砝码数减游码指的示数
C.仅等于砝码数D.无法准确读出物体的质量
(3).若小明改正错误称量后,用天平测量液体的质量.当天平平衡时,放在右盘中的砝码大小和游码的位置如图b中甲所示,则称得烧杯和液体的质量m为________g.
(4).用量筒测量液体的体积.将烧杯中的液体全部倒入量筒中,液面达到的位置如图b中乙所示,则该液体的体积V为________mL.尽管体积测量方法正确,但大家在对实验过程及结果进行评估时,发现液体的体积测量值比它的实际值要________,如果按这种方案,测得的密度值__________。(两空均选填“偏大”或“偏小”).
(5).他们对测量方法进行修正后,测出了几组实验数据,并根据测量结果作出了“m-V”图象,如下图所示.由图象可知该液体的密度为________kg/m3 通过查表对照知该液体可能是________.
 

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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(修辞). 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(对称的) 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(机警的). 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.
【小题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.
【小题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
【小题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
【小题4】 As is meant by the author, thorns of a rose_________.
A.protect the rose from harmB.symbolize reduced love
C.add a new element to the image of loveD.represent objects of one’s affection
【小题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

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