问题 选择题

下列说法中正确的是(  )

A.穿过某一个面的磁通量为零,该处磁感强度也为零

B.穿过任何一个平面的磁通量越大,该处磁感强度也越大

C.穿过垂直于磁感强度方向的某面积的磁感线条数等于磁感强度

D.当平面跟磁场方向平行时,穿过这个面的磁通量必为零

答案

A、当平面与磁场平行时,穿过某一个面的磁通量为零,但磁感强度不为零.故A错误.

    B、穿过任何一个平面的磁通量越大,该处磁感强度不一定越大,也有可能这个平面在磁场垂直方向投影面积大.故B错误.

    C、穿过垂直于磁感强度方向的某面积的磁感线条数等于磁通量,而穿过垂直于磁感强度方向的某单位面积的磁感线条数才等于磁感强度.故C错误.

    D、当平面跟磁场方向平行时,没有磁感线穿过这个平面,则穿过这个面的磁通量必为零.故D正确.

故选D

阅读理解

阅读理解。

    It's good to share your feelings with others. No matter whether your feelings are good or not, it can

also help you to get closer to people who you care about and who care about you.

    But how to share your feelings? First, you should focus (定焦点) on your feelings. You can't tell your

friends what's inside your backpack if you don't know what's in it yourself. Feelings are the same way.

Before you share them with someone, you should know what feelings you have. You can make a list of

feelings in your head or by writing it out on a piece of paper or even by drawing pictures. What bothers

(烦扰) you? Does it make you sad or angry? Do you feel this emotion (情感) only once or many times?

When you do this, it might help you to remember something that happend and think about how it makes

you feel. Then you can say "I feel sad that my friend won't play with me." or "I feel angry with my

classmates..."

    Do you know why you should talk about your feelings? If you always keep your feelings inside,

especially sadness, nervousness or anxiety (焦虑), it can even make you feel sick. But if you talk with

someone who cares about you, like your mom and dad, you'll feel much better. Your parents want to

know what's hapening in your life because they love you.  But if you don't want to talk with them, please

talk with your friends. They will help you.

根据短文内容,判断正(T)误(F)。

( )1. Don't share your feelings with others.

(     )2. Before you share your feelings with others, you should focus on your feelings.

(     )3. You can draw pictures about your feelings.

( )4. If you always keep your feelings inside, you may feel sick.

(     )5. You can only share your feelings with your parents.

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