题干

李明等几位同学准备探究“弹簧弹性势能的大小与什么因素有关”.同学们猜想:弹簧弹性势能可能与弹簧长度变化量和弹簧粗细有关.他们设计的实验装置如图,弹簧左端固定在墙上,放在水平面上,水平面A点左侧光滑,右侧粗糙.物体P压缩弹簧到B点后从静止释放,运动到C点弹簧恢复到原长与物体脱离,物体运动到D点停止.请补充完成他们的探究过程:

 

(1)对同一根弹簧,物体P压缩弹簧至B点,从静止释放,运动到D点.测量____ 之间的距离和____ 之间的距离,并改变____ 之间的距离,测多组数据,分析数据得到:弹簧长度变化量越大,弹性势能越大.

(2)对原长相同、只有粗细不同的两根弹簧,物体P分别压缩弹簧至同一位置B点,从静止释放,运动到D点.分别测量____ 之间的距离,改变压缩量,重复试验,分析数据得到:弹性势能与弹簧粗细有关.

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    Sometimes you'll hear people say that you can't love others until you love yourself. Sometimes you'll hear people say that you can't expect someone else to love you until you love yourself. Either way, you've got to love yourself first and this can be tricky. Surely we all know that we're the apple of our parents' eyes, and that our Grandmas think we're great talents and our Uncle Roberts think that we will go to the Olympics,but sometimes it's a lot harder to think such nice thoughts about ourselves. If you find that believing in yourself is a challenge, it is time you build a positive self-image and learn to love yourself.

    Self-image is your own mind's picture of yourself. This image includes the way you look, the way you act, the way you talk and the way you think. Interestingly, our self-images are often quite different from the images others hold about us. Unfortunately, most of these images are more negative than they should be. Thus changing the way you think about yourself is the key to changing your self-image and your whole world.

    The best way to defeat a passive self-image is to step back and decide to stress your successes. That is, make a list if you need to, but write down all of the great things you do every day. Don't allow doubts to occur in it.

    It very well might be that you are experiencing a negative self-image because you can't move past one flaw or weakness that you see about yourself. Well, roll up your sleeves and make a change of it as your primary task. If you think you're silly because you aren't good at math, find a tutor. If you think you're weak because you can't run a mile, get to the track and practice. If you think you're dull because you don't wear the latest trends, buy a few new clothes. But remember, just because you think it doesn't mean it's true.

    The best way to get rid of a negative self-image is to realize that your image is far from objective, and to actively convince yourself of your positive qualities. Changing the way you think and working on those you need to improve will go a long way towards promoting a positive self-image. When you can pat yourself on the back,you'll know you're well on your way. Good luck!