题干

在甲图中,带正电粒子从静止开始经过电势差为U的电场加速后,从G点垂直于MN进入偏转磁场.该偏转磁场是一个以直线MN为上边界、方向垂直于纸面向外的匀强磁场,磁场的磁感应强度为B,带电粒子经偏转磁场后,最终到达照相底片上的H点,如图甲所示,测得G,H间的距离为d,粒子的重力可忽略不计.

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(A)信息归纳:阅读下面的短文,根据短文的内容完成信息卡。

    Starting high school can be difficult.Everyone is nervous and nobody knows where to go for classes.Thinking about making new friends might make you feel nervous, too. But don't worry, because you are not alone. You are going to school with a group of students of your age, and we have several tips(贴士) for you to follow.

    Forget your fear and just talk to someone.

    It is easier said than done. But try to take a deep breath and find your voice. Don't be afraid to approach(接近) people. First, you should introduce yourself before starting a conversation about something you have in common. Then, sit in the middle of the classroom with as many new friends around you as possible.

    Join clubs.

    Clubs are good places to make friends. Try to make friends in the club that interest you..If you don't join anything, you will be just going to class and then going home.Being in a club makes you more social.

    Stay clean.

    No one likes a bad smell that could knock someone over.Shower every day, brush your teeth and wash your hair. You are supposed to make yourself look clean and tidy, whatever you wear.

    Be respectful(尊重的) of people's differences.

    Everyone has his or her own opinion of the world.And everyone believes in different things.It's a good thing to have different friends with different opinions because you can each share your own.

Information Card

The number of tips that the writer gives

____.

The thing that might make you feel nervous.

____.

The first thing you should do before starting a conversation about something you have in common.

____.

The good places to make friends

____.

The reason why it's a good thing to have different friends with different opinions

____.