某同学拟用电流表和电压表测定电源电动势和内电阻,备有:干电池一只(电动势约为1.

题型:实验题

问题:

某同学拟用电流表和电压表测定电源电动势和内电阻,备有:干电池一只(电动势约为1.5V,内阻约2Ω),电压表一只(0~3V,内阻约3kΩ),电流表一只(0~0.6A,内阻约1.0Ω),滑动变阻器有R1(0~10Ω,2A)和R2(0~100Ω,0.1A)各一只,开关一个,导线若干。

(1)实验中滑动变阻器应选用_________(选填“R1”或“R2”)。

(2)为了最大限度的减小实验误差,请在下图的方框内画出该实验的最合理的电路图。

(3)该同学记录数据如下表,请根据这些数据在上图作出U-I图像,根据图线得到被测电源电动势E=________V;内阻r=________Ω。

考点:实验:测定电池的电动势和内阻
题型:实验题

B Customs of Bulgaria: Marriage and Family保加利亚习俗:婚姻与家庭
The average age for women to marry is between 18 and 25.25 tend to (1) when somewhat older. A church wedding often (2) the legal civil ceremony, and a large reception, which often involves (3) music and dancing, is held in the evening. Wedding traditions include (4) money on the bride’s dress to represent future prosperity, the groom (5) the bride at her home, and the couple pulling on opposite (6) of a loaf of bread—whoever gets the largest piece will be (7) boss of the family. Honeymoons are a new tradition.
The principle (8) mutual support is valued in the Bulgarian family. The elderly are (9) cared for by their adult children. Unmarried adults live with their (10) and many newly married couples live with one set of parents (11) they are able to get housing of their own. Most families (12) urban areas live in apartments, which are in short
supply, while (13) in rural areas usually have their own houses. Many village houses (14) owned by families who live in urban areas, who use them_ (15) summer and weekend retreats, or for retired parents.
Most families in (16) areas do not have more than two children, while families in (17) areas tend to be larger. Grandparents play an important role in (18) care, particularly in urban areas, where most women work outside the (19) . Men of the younger generation have begun to help with household (20) , once considered only women’s responsibility.

题型:实验题

《素问.脉要精微论》提及人的异常面色有()。

A.如白裹朱

B.盐

C.蓝

D.黄土

E.重漆色

题型:实验题

“吾日三省吾身”是出自()的名句。

题型:实验题

(10分)某同学用图示实验装置验证质量一定时系统的加速度与合外力的关系,小车内盛有沙子,沙桶和沙桶内沙子的总质量记为m,小车及车内沙子的总质量记为M,在实验中保持m与M之和不变,将沙桶和沙桶内沙子总重力视为系统所受合外力F,先通电源,再释放纸带,系统加速度a由纸带计算得到;该同学从车子中取出一些沙子,放入沙桶中,改变F的大小,重复多次,测得多组(a,F)。

次数123456
a/(m/s2)0.50.741.011.241.481.75
mg/(N)0.10.150.200.250.300.35
⑴该同学在实验中缺了一个必要步骤是                                                    

⑵通过表格中的数据在下图坐标系中画出a-F图象,利用图象求出M+m=                 kg;

⑶该实验研究的对象是                ,所受的合外力是                

题型:实验题

书面表达。

    假如你是大学一年级新生李华。开学之初,你的英语老师Ms Li希望了解每位同学的

英语学习情况,并征求教学建议。请按以下要点用英语给她写一封信。

1.对英语学习的认识;

2.自己目前的英语水平;

3.自己英语学习存在的主要问题;

4.对英语教学的两点建议。

注意:

1.词数100左右;

2.信的开头和结尾已给出。

Dear Ms Li,

    I'm very happy to have you as our English teacher. _________________________________

_________________________________________________________________________

     Thank you!    

                                                                                                                                    Li Hua

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