题干

(2011年山东济南模拟)如图9-2-11所示,一轻质横杆两侧各固定一金属环,横杆可绕中心点自由转动,老师拿一条形磁铁插向其中一个小环,后又取出插向另一个小环,同学们看到的现象是(  )

图9-2-11

A:磁铁插向左环,横杆发生转动

B:磁铁插向右环,横杆发生转动

C:无论磁铁插向左环还是右环,横杆都不发生转动

D:无论磁铁插向左环还是右环,横杆都发生转动

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答案(点此获取答案解析)

B

同类题5

    Good evening, ladies and gentlemen. Welcome to the nine o’clock Mystery Hour. Today we’ll show you two British stories. We hope you'll enjoy them.
    About 900 years ago two green children arrived in a small village in south England. Their eyes and skin were green and they spoke a strange language. They were very tired and weak, so the people of the village looked after them. The boy died a year later, but the girl grew strong and lived the rest of her life there. And her skin color turned back to normal day by day. Scientists say that sometimes of people don't have enough food to eat for a long time, their skin goes very pale and can turn green.
    Loch Ness is the largest lake in Scotland. It’s a very deep and cold lake. For hundreds of years, people have talked about a monster(怪物) called Nessie which lives in the lake. About seventy years ago, two people saw something moving in the lake. They said that the animal was playing and rolling around in the water. Since then many people say they have seen the monster. Their descriptions are always the same. It looks like a dinosaur, with a very long neck and a small head. It has a big bump(肿块)on its back. People have tried to photograph the animal, but the pictures have not been very clear. Scientists don’t know whether there is a monster or not. Some say it may be a whale or a very large fish. Some think it’s a snake. Others say there’s nothing at all— nothing but people’s imagination. Maybe we’ll never know what's in Loch Ness.