题干

在测定一根粗细均匀合金丝Rx的电阻率的实验中.

Ⅰ.利用螺旋测微器测定合金丝的直径,示数如图(a)所示,则可读得合金丝的直径为____ mm.

Ⅱ.待测合金丝Rx的电阻约为5Ω.提供的仪器有:

A.电压表V(内阻约为10kΩ,量程为3V)

B.电流表A1(内阻约为3Ω,量程为0.6A)

C.滑动变阻器R(阻值为0~5Ω,额定电流为2A)

D.电源E(电动势为5V,内电阻为1Ω)

E.一个开关、若干导线

①某同学根据以上仪器,按图(b)连接实验线路,现请你用笔在图(b)中画一条线将电路补完整.____

②考虑到电路中所用电表不是理想电表,其测量结果比真实值偏____(填“大”或“小”).

上一题 下一题 0.0难度 选择题 更新时间:2019-08-13 12:44:15

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0.609,,小

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Evaluating (评价)Sources of health Information

Makinggood choices about your own health requires reasonable evaluation. A key firststep in bettering your evaluation ability is to look carefully at your sourcesof healthy information. Reasonable evaluation includes knowing where and how tofins relevant information, how to separate fact from opinions, how to recognizepoor reasoning, and how to analyze information and the reliability of sources.____ 

Goto the original source. Media reports often simplify the results of medicalresearch. Find out for yourself what a study really reported, and determinewhether it was based on good science. Think about the type of study.____

Watchfor misleading language. Some studies will find that a behavior “contributesto” or is “associated with” an outcome; this does not mean that a certaincourse must lead to a certain result.____ Carefully read or listen toinformation in order to fully understand it.

Useyour common sense. If a report seems too good to be true, probably it is. Beespecially careful of information contained in advertisements.____ Evaluate “scientific” statements carefully,and be aware of quackery(江湖骗术).____ Friends and family members can be a greatsource of ideas and inspiration, but each of us needs to find a healthylifestyle that works for us.

Developingthe ability to evaluate reasonably and independently about the health problemswill serve you well throughout your life.

A.The goal of an ad is to sell yousomething.

B.Make choices that are right for you.

C.And examine the findings of theoriginal research.

D.Be sure to work through the criticalquestions.

E.Distinguish between research reportsand public health advice.

F.The following suggestions can help yousort through the health information you receive from common sources.

G.Be aware that information may also beincorrectly explained by an author's point of view.