题干

如图a所示,水平面上质量相等的两木块A,B,用轻弹簧相连接,这个系统处于平衡状态.现用一竖直向上的力F拉动木块A,使木块A向上做匀加速直线运动(如图b),研究从力F刚作用在木块A瞬间到木块B刚离开地面瞬间的这一过程,并选定该过程中木块A的起点位置为座标原点.则下面图中能正确表示力F和木块A的位移x之间关系的图是(   )

A:

B:

C:

D:

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A

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    Sometimes the toughest thing about feelings is sharing them with others.Sharing your feelings helps you whether your feelings are wonderful or terrible.Sharing also helps you to get closer to people you care about and who care about you.But how?

    You can't tell your friends what's inside your backpack if you don't know what's in there yourself.Feelings are the same way.Before you can share them with anyone,you have to figure out what feelings you have.

    Making a list of your feelings can help.You can do this in your mind or by writing it out or even by drawing pictures.Is something bothering you? Does it make you frustrated or terrified? Do you feel this emotion only once in a while or much of the time?

    The way a person feels inside is important.If you keep feelings locked inside,it can even make you feel sick! But if you talk with someone who cares for you,you will almost always start to feel better.It doesn't mean your problems and worries magically disappear,but at least someone else knows what's bothering you and can help you find solutions.

    Your mom and dad want to know if you have problems and what's happening in your life.But what if a kid doesn't want to talk with parents? Then find another trusted adult,like a relative or a teacher at school.Maybe this person can help you talk with your parents about your problem or concern.

    Once you know who you can talk with,you'll want to pick a time and place to talk.You can talk publicly in your family.But some kids are more private than others and they will feel shy about sharing their feelings.Then find a quiet place or write it down on a piece of paper.A kid doesn't have to share every feeling he or she has.