题干

图示电路中,电源电动势为E,内阻为r,R1、R2为定值电阻,R3为可变电阻,C为电容器.在可变电阻R3由较大逐渐变小的过程中(   )

A:电容器充电

B:流过R2的电流方向是由b到a

C:电容器的电荷量在逐渐减少

D:电源内部消耗的功率变小

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C

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    It was one of those terribly hot days in Baltimore. Needless to say, it was too hot to do anything outside. But it was also scorching in our apartment. This was 1962, and I would not live in a place with an air conditioner for another ten years. So my brother and I decided to leave the apartment to find someplace indoors. He suggested we could see a movie. It was a brilliant plan.

    Movie theaters were one of the few places you could sit all day and—most important —sit in air conditioning. In those days, you could buy one ticket and sit through two movies. Then, the theater would show the same two movies again. If you wanted to, you could sit through them twice. Most people did not do that, but the manager at our theater. Mr. Bellow did not mind if you did.

    That particular day, my brother and I sat through both movies twice, trying to escape the heat. We bought three bags of popcorn and three sodas each. Then, we sat and watched The Music Man followed by The Man Who Shot Liberty Valance. We'd already seen the second movie once before. It had been at the theater since January, because Mr. Bellow loved anything with John Wayne in it.

    We left the theater around 8, just before the evening shows began. But we returned the next day and saw the same two movies again, twice more. And we did it the next day too. Finally, on the fourth day, the heat wave broke.

    Still, to this day I can sing half the songs in The Music Man and recite half of John Wayne and Jimmy Stewart's dialogue from The Man Who Shot Liberty Valance! Those memories are some of the few I have of the heat wave of 1962. They're really memories of the screen, not memories of my life.