题干

如图甲所示电路中,有两根导线尚未连接,请用笔画线代替导线补上,补上后要求:①电压表测小灯泡两端电压;②闭合开关S,向a端移动滑动变阻器的滑片P,小灯变亮③在图乙中的方框内画出电路图
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解:

由题知,灯泡与滑动变阻器串联,滑片向a端移动,灯泡变亮,说明电路中电流变大,则滑动变阻器接入电路的电阻变小,故将变阻器的左下接线柱与灯泡右边接线柱相连,并将电压表并联在灯泡两端;再根据实物连接画出电路图,如下图所示:

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    Are you suffering from FOMO—that is, Fear Of Missing Out? Research shows that a growing number of young people are, with worrying consequences for their sleep and schoolwork.

    ____You aren't able to do your best unless you sleep well. Most experts agree that the optimum(最适宜) number of hours is eight, and this has been accepted as common sense for as long as I can remember. However, I was young once and know most of you get much less sleep than that.

    I read an interesting article in a teachers' magazine recently.____Worryingly, the results showed that teenagers are facing a new problem. They may go to bed and get up at appropriate times, but a growing number are waking up in the middle of the night, not to use the bathroom or have a snack, but because of FOMO.

    According to the article, the number of students waking up during the night to check social media is growing. Afraid of missing a comment or opportunity to take part in a chat, teenagers are waking at all times of the night, going online and getting involved.____

    Experts are worried about this growing trend and the report reveals some worrying statistics: 23% of 12-to 15-year-olds wake up nearly every night to use social media.____One in third of the students are constantly tired and unable to function to their full capacity.

    So I'd like to ask you to be responsible when it comes to social media. Switch off your devices at night. The world won't end and your social media will be waiting to greet you in the morning!____

A.But things are getting out of hand.

B.They did a study of 848 students in Wales.

C.Another 15% wake up at night once a week for the same reason.

D.I give you my word that you won't have missed anything important.

E.All happens when they should be sound asleep.

F.FOMO is the fear that everyone else is having more fun and more excitement than you.

G.Everybody knows how important it is for students to get a good night's sleep every night.