题干

 如图,一重力不计的挂衣钩“吸”在竖直墙上,钩上挂着物体保持静止.请画出挂衣钩在竖直方向上受力的示意图.(画图时,用实心点O表示力的作用点)

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解:挂衣钩重力不计,在竖直方向上受到物体对它竖直向下的拉力和竖直向上的摩擦力的作用,其作用点都可以画在重心上,过挂衣钩的重心分别沿竖直向下和竖直向上的方向画一条有向线段,分别用F和f表示,因为这两个力是一对平衡力,作图时两条线段长度要相等.如图所示

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    Although problems are a part of our lives, it certainly doesn't mean that we let them rule our lives forever. One day or the other, you'll have to stand up and say – problem, I don't want you in my life.

    ____ Problems with friends, parents, girlfriends, husbands, and children – the list goes on. Apart from these, the inner conflicts within ourselves work, too. These keep adding to our problems. Problems come in different shapes and colors and feelings.

    But good news is that all problems can be dealt with. Now read on to know how to solve your problems.

    Talk, it really helps. What most of us think is that our problem can be understood only by us and that no talking is going to help.____Talking helps you move on and let go.

    Write your problems.____When you write down your problems, you are setting free all the tension from your system. You can try throwing away the paper on which you wrote your problems. By doing this, imagine yourself throwing away the problems from your life.

    Don't lose faith and hope. No matter what you lose in life, don't lose faith and hope. Even if you lose all your money, family… you should still have faith.____

    Your problems aren't the worst. No matter what problem you get in life, there're another one million people whose problems are huger than yours.____ Your problems might just seem big and worse, but in reality they can be removed.

    Go about and solve your problems because every problem, however big or small, always has a way out.

A. But the truth is that when you talk about it, you're setting free the negative energies have been gathering within you.

B. When we have a problems, a pressing, critical, urgent, life-threatening problem, how do we try and solve it?

C. Tell yourself: when they can deal with them, why can't I?

D. Of course, we've been fighting troubles ever since we were born.

E. We can often overcome the problem and achieve the goal by making a direct attack.

F. Having a personal diary can also be of huge help if you don't want a real person to talk with.

G. With faith and hope, you can rebuild everything that you lose.