需要100g的酒精,不用天平,只用量筒,应该量出酒精的体积是 ______cm3

题型:填空题

问题:

需要100g的酒精,不用天平,只用量筒,应该量出酒精的体积是 ______cm3.(酒精的密度是0.8×103千克/米3).

考点:体积的测量,量筒的使用密度公式的应用
题型:填空题

有效焦点与实际焦点的关系,正确的描述是()

A.实际焦点一定等于有效焦点

B.实际焦点的长度越长,有效焦点也就越大

C.靶角越小,有效焦点面积也就越小

D.实际焦点一定大于或等于有效焦点

E.实际焦点与有效焦点无定量关系

题型:填空题

  运用联想、想象,丰富下面的语句,其中要有一个比喻句或拟人句;只要保留原词语的电(闪)、雷、雨(水)即可。

  原句:闷热的夜,令人窒息。忽然,电闪,雷鸣,雨水如注。

 ______________________________________________________

题型:填空题

We can achieve knowledge either actively or passively(被动地). We achieve it actively by direct experience, by testing and proving an idea, or by reasoning.
We achieve knowledge passively by being told by someone else. Most of the learning that takes place in the classroom and the kind that happens when we watch TV or read newspapers or magazines is passive. Conditioned as we are to passive learning, it’s not surprising that we depend on it in our everyday communication with friends and co-workers.
Unfortunately, passive learning has a serious problem. It makes us tend to accept what we are told even when it is little more than hearsay and rumor(谣言).
Did you ever play the game Rumor? It begins when one person writes down a message but doesn’t show it to anyone. Then the person whispers it, word for word, to another person. That person, in turn, whispers it to still another, and so on, through all the people playing the game. The last person writes down the message word for word as he or she hears it. Then the two written statements are compared. Typically, the original message has changed.
That’s what happens in daily life. The simple fact that people repeat a story in their own words changes the story. Then, too, most people listen imperfectly. And many enjoy adding their own creative touch to a story, trying to improve on it, stamping(打上标记)it with their own personal style. Yet those who hear it think they know.
This process is also found among scholars and authors: A statement of opinion by one writer may be re-stated as fact by another, who may in turn be quoted by yet another; and this process may continue, unless it occurs to someone to question the facts on which the original writer based his opinion or to challenge the interpretation he placed upon those facts.
小题1:According to the passage, passive learning may occur in _______.
A.doing a medical experimentB.solving a math problem
C.visiting an exhibitionD.doing scientific reasoning
小题2:The underlined word “it” in Paragraph 2 refers to _____.
A.active learningB.knowledge C.communicationD.passive learning
小题3:The author mentions the game Rumor to show that _____.
A.a message may be changed when being passed on
B.a message should be delivered in different ways
C.people may have problems with their sense of hearing
D.people tend not to believe in what they know as rumor
小题4:What can we infer from the passage?
A.Active learning is less important.B.Passive learning may not be reliable.
C.Active learning occurs more frequently.
D.Passive learning is not found among scholars.
题型:填空题

“水会增大物体间的摩擦力吗?”多数人的答案是:不会, 许多人都知道这样的常识:油漆过的地板上有水时,人很容  易滑倒,但也有相反的事例,例如爬过树的人都知道:手上出汗时,会感觉到手与树之间的摩擦力变大了。水到底可以增大还是减小物体间的摩擦呢?比较上述事例发现,油漆过的木板表面不吸水,树木(可看做未油漆过的木板)表面吸水,所以探究水对摩擦力大小的影响,应分为两种情况:

猜想一:在不吸水的木板表面,有水时的摩擦力可能比无水时的摩擦力小,    

猜想二:在吸水的木板表面,有水时的摩擦力可能比无水时的摩擦力大,

为了验证上述两个猜想,请你完成下列问题:

(1)将所需实验器材补充完整,器材:油漆过的木板、未油漆过的木板、带有挂钩的木块、盛水的  烧杯及___________

(2)设计记录实验数据的表格。

题型:填空题

通过多机协作,可以共同解决一个复杂的大问题。在奔腾芯片中,支持这项技术的是______。

A.超标量技术

B.超流水技术

C.多线程技术

D.多重处理技术

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