问题 补全对话,情景问答

补全对话.

A: Do you have a pen pal?

B: Yes, I do. I have a boy pen pal. He's Pete.

A: ___1___?

B: He comes from Toronto, Canada.

A: ___2___?

B: He's tall with medium build, curly hair and blue eyes. Here is a photo of him.

A: ___3___?

B: He loves sports shows. Sports are his favorite.

A: ___4___?

B: Yes, I do. I want to go to Toronto and visit him next vacation.

A: ___5___?

B: It's warm in spring and not hot in summer. The weather is nice.

A: OK, I hope you have a good trip!

B: Thank you.

答案

1. Where is he from / Where does he come from

2. What does he look like

3. What does he think of sports shows

4. Do you want to visit him

5. How is the weather / What is the weather like

问答题

(1)甲同学要把一个量程为200μA的直流电流计G,改装成量范围是0~4V的直流电压表.

①她按图1所示电路、用半偏法测定电流计G的内电阻rg,其中电阻R0约为1kΩ.为使rg的测量值尽量准确,在以下器材中,电源E应选用______,电阻器R1应选用______,电阻器R2应选用______(选填器材前的字母).

A.电源(电动势1.5V)B.电源(电动势6V)

C.电阻箱(0~999.9Ω)D.滑动变阻器(0~500Ω)

E.电位器(一种可变电阻,与滑动变阻器相当)(0~5.1kΩ)

F.电位器(0~51kΩ)

②该同学在开关断开情况下,检查电路连接无误后,将R2的阻值调至最大.后续的实验操作步骤依次是:______,______,______,______,最后记录R1的阻值并整理好器材.(请按合理的实验顺序,选填下列步骤前的字母)

A.闭合S1

B.闭合S2

C.调节R2的阻值,使电流计指针偏转到满刻度

D.调节R2的阻值,使电流计指针偏转到满刻度的一半

E.调节R1的阻值,使电流计指针偏转到满刻度的一半

F.调节R1的阻值,使电流计指针偏转到满刻度

③如果所得的R1的阻值为300.0Ω,则图1中被测电流计G的内阻rg的测量值为______Ω,该测量值______实际值(选填“略大于”、“略小于”或“等于”).

④给电流计G______联(选填“串”或“并”)一个阻值为______kΩ的电阻,就可以将该电流计G改装为量程4V的电压表.

(2)乙同学要将另一个电流计G改装成直流电压表,但他仅借到一块标准电压表V0、一个电池组E、一个滑动变阻器R′和几个待用的阻值准确的定值电阻.

①该同学从上述具体条件出发,先将待改装的表G直接与一个定值电阻R相连接,组成一个电压表;然后用标准电压表V0校准.请你画完图2方框中的校准电路图.

②实验中,当定值电阻R选用17.0kΩ时,高整滑动变阻器R′的阻值,电压表V0的示数是4.0V时,表G的指针恰好指到满量程的五分之二;当R选用7.0kΩ时,调整R′的阻值,电压表V0的示数是2.0V,表G的指针又指到满量程的五分之二.由此可以判定,表G的内阻rg是______kΩ,满偏电流Ig是______mA.若要将表G改装为量程是15V的电压表,应配备一个______kΩ的电阻.

单项选择题