题干

如图所示,多匝线圈和电池的内阻均为零,两个电阻的阻值均为R,开关S开启,电路中的电流为I0,现将S闭合,于是线圈中产生自感电动势,此自感电动势(   )

A:有阻碍电流的作用,最后电流由I0减小为零

B:有阻碍电流的作用,最后总电流小于I0

C:有阻碍电流增大的作用,因而电流保持I0不变

D:有阻碍电流增大的作用,但电流还是要增大到2I0

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D

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                                                                                Get a Thorough Understanding of Oneself.

    In all one's life lime it is oneself, that one spends the most time being with or dealing with.____.

    When you are going upwards in life you tend to overestimate yourself. It seems that everything you seek for is within your reach,____ It's likely that you think it wise for yourself to stay away from the outer world. Actually, to get a thorough understanding of oneself, you may as well keep the following tips in mind.

Gain a correct view of oneself.

    You may look forward hopefully to the future but be sure not to expect too much, for dreams can never be fully realized. You may be courageous to meet challenges but it should be clear to you where to direct your efforts.____

Self-appreciate.

    Whether you compare yourself to a towering tree or a blade of grass, a high mountain or a small stone, you represent a state of nature.____ If you earnestly admire yourself you'll have a real sense of self-appreciation.

____ In time of anger, do yourself a favor by releasing it in a quiet place so that you won't be hurt by its flames; in time of sadness, do yourself a favor by sharing it with your friends so as to change a bad mood into a cheerful one; in time of tiredness, do yourself a favor by getting a good sleep.

Get a full control of one's life.

    Then one will find one's life full of color and favor.

A. It has its own value.

B. Do oneself a favor when it's needed.

C. Do yourself a favor when you resist the attack of illness.

D. But it is precisely oneself that one has the least understanding of.

E. Especially if it is well within your reach, you are just too blind to see it.

F. When you are going downhill you tend to underestimate yourself for your own incompetence,

G. o long as you have a perfect knowledge of yourself, there won't be difficulties you can't overcome.