题干

以下说法中正确的是(   )

A:从公式I= UR 可知,导体中电流跟导体两端的电压成正比,跟导体的电阻成反比

B:对于导体,只要其两端电势差为零,电流也必为零

C:电源的电动势大,表征把其他形式的能转化为电能的数量就多

D:电源电动势越大,电源两极间的电压一定越高

上一题 下一题 0.0难度 选择题 更新时间:2018-03-07 12:55:49

答案(点此获取答案解析)

A,B

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完形填空

    Lord Nithsdale was put into prison in 1716 because he was against King George I. As a (n)1 he was sentenced to death . His wife Winifred couldn't imagine life 2 her husband , so she was 3to do anything to save him .

    She was determined to 4the King and beg him for her husband's life, but the King didn't agree. Winifred refused to 5In desperation, she came up with a more 6 plan.  She visited her husband alongside her maid, her friends Mrs. Mills and Mrs. Morgan. Only two visitors at a time were allowed to enter the room. They took advantage of this 7, going into and out of the room many times to 8 the guards. She also gave the guards money and drink.

    9 inside the prison Winifred pulled out some10clothes and dressed her husband up as one of the11 Mrs. Mills. Mrs. Mills was then brought in, emotional and with her 12 buried in her handkerchief.  Lord Nithsdale then was led out by his wife, also holding the handkerchief to his eyes. This was very 13 or the guards would notice that one of the women had a long 14 ! Fortunately everyone managed to get outside at last.

    Winifred then returned to the room and 15 to be in an emotional conversation with her husband. After a suitable period of time had passed for her husband to leave ,she left the room and got some 16for herself by telling the guards that her husband was praying (祈祷) and should not be 17 This was a clever action as it allowed the 18 to go unnoticed for longer.

    To complete the clever escape and appear 19 they gave a tearful goodbye. Lord Nithsdale and his wife20and managed to leave the country together.