题干

在如图所示的电路中,电源电压保持不变,闭合电键S,电路正常工作,下列一些数据中:①电压表V的示数;②电压表V示数与电流表A1示数的比值;③电压表示数V与电流表A示数的乘积;④电流表A1示数与A示数的比值;⑤电压表示数V与电流表A示数的比值.

当滑动变阻器R1的滑片P向右移动时,变大的是____;变小的是____.(均选填相关数据的序号)

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答案(点此获取答案解析)

②④⑤,③

同类题3

阅读下列短文,从每题所给的四个选项 (A 、B 、C  和 D )中,选出择最佳选项。

    Many people who work in London prefer to live outside it, and to go in to their offices or schools every day by train, car or bus, even though this means they have to get up early in the morning and reach home late in the evening.

    One advantage of living outside London is that houses are cheaper. Even a small flat in London without a garden costs quite a lot to rent (租住). With the same money, one can get a little house in the country with a garden of one's own.

    Then, in the country one can rest from the noise and hurry of the town. Even though one has to get up earlier and spend more time in trains or buses, one can sleep better at night and during weekends and on summer evenings, one can enjoy the fresh, clean air of the country. If one likes gardens, one can spend one's free time digging, planting, watering and doing the hundred and one other jobs which are needed in a garden. Then, when the flowers and vegetables come up, one has the reward of sharing the secret of Nature.

    Some people, however, take no interest in country things:for them, happiness lies in the town, with its cinemas and theatres, beautiful shops and busy streets, dance halls and restaurants. Such people would feel that their life was not worth living if they had to live it outside London. An occasional walk in one of the parks and a fortnight's (two weeks) visit to the sea every summer is all the country they want: the rest they are quite prepared to leave to those who are glad to get away from London every night.