问题 计算题

如图所示的电路中,E=10 V,R1=4 Ω,R2=6 Ω,电池内阻不计,C1=C2=30 μF.先闭合开关S,待电路稳定后再断开S,求断开S后通过电阻R1的电荷量.

答案

4.2×10-4 C

S闭合时,I=

UC1=IR2=6 V                                 (2分)

由于C2被S短路,其两端电压UC2=0

S断开待电路稳定后,由于电路中无电流,故UC1′=UC2

=10 V                                      (2分)

电容器C2上增加的电荷量为:

ΔQ2=C2(UC2′-0)=30×10-6×10 C=3×10-4 C.(2分)

电容器C1上增加的电荷量为:

ΔQ1=C1(UC1′-UC1)=30×10-6×4 C

=1.2×10-4 C.                               (2分)

通过R1的电荷量

Q=ΔQ1+ΔQ2=4.2×10-4 C.                    (2分)

阅读理解

阅读理解。

     Cyber language is popular among Chinese netizens, who create English words to reflect novel

phenomenon in society.

     "Geilivable", combining pinyin of Chinese characters Geili (giving strength) with the English suffix

for adjectives, literally means "giving power" or "cool". Similarly, "hengeilivable" means "very cool",

and "ungeilivable" means "dull, not cool at all". "Antizen" refers to the group of college graduates who,

earning a small salary and living in small rented apartments, are like the tiny and laborious ants.

     David Tool, a professor with the Beijing International Studies University said it's very interesting to

combine Chinese with English to create new words. "English is no longer mysterious to the Chinese

people. They can use the language in a flexible way according to their own experiences," he said. Chinese

words and expressions were created, as well, by netizens. One example was "Suan Ni Hen". This three-

character expression, which originally meant "you win" with the first character carrying the same

pronunciation as garlic in Chinese, is used to satirize (讽刺) high garlic and food prices this winter.

     Chinese people use the character "bei" before a verb to show a passive voice, and it is used by netizens

to show the helplessness in front of false conclusions and fake media reports. For instance, "zisha" means

"suicide" while "beizisha" means "be officially presumed to have committed suicide", and "xiaokang" means

"fairly comfortable life" while "beixiaokang" means "be said to be living a fairly comfortable life".

     Wu Zhongmin, a professor at the Party School of the Central Committee of the Communist Party of

China, saw the phenomenon of word creation as a natural response of young people to social issues. "Cyber

language is more vivid and it shortens people's distances," he said.

1. The passage mainly tells us that _____.

A. cyber language is popular among all people

B. cyber language is of great fun

C. cyber language needs to be taught at college

D. cyber language in China is popular for it's relation with society

2. Which of the following is NOT true?

A. Ungeilivable means "dull, not cool at all".

B. Antizens live in small rented apartments with small salaries.

C. Suan Ni Hen refers to the highest food prices ever.

D. Beixiaokang means "be said" to be living a comfortable life.

3. What can we infer from the phenomenon of word creation?

A. It's getting more difficult to understand cyber language.

B. Young people are more likely to respond to nature.

C. Social phenomena are more easily reflected in cyber language.

D. The best way to create new cyber words is to combine Chinese and English.

4. Chinese netizens created English words by _____.

A. combining pinyin of Chinese characters with the English suffix

B. using the character carrying the same pronunciation

C. combining Chinese characters with the English

D. putting the character"bei" before an English word

单项选择题