题干

如图所示,边长为L的正方形线框旋转在光滑绝缘的水平面上,空间存在竖直向下的匀强磁场,MN和PQ为磁场边界,磁场宽度为
2
2
 L.开始时,线框的顶点d恰在磁场边界上,且对角线bc与磁场边界平行,现用外力使线框沿与磁场边界垂直的方向匀速运动,则在穿过磁场的过程中,线框中的电流I(以逆时针方向为正)和外力的功率P随时间变化正确的图象为(    )

A:

B:

C:

D:

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A

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    When we think of leadership, we often think of strength and power. But what are these really, and how do they operate?

    Leadership today is not about forcing others to do things. If this is even possible, it is short-term. If you order someone to do something against their will, they may do it because they feel they must, but the anger they feel will do more harm in the long-term. They will also experience fear.

    Fear causes the thinking brain to shut down, making the person unable to function at his or her best. If they connect you with this emotion of fear, they will become less functional around you, and you will have succeeded in not only shooting yourself in the foot, but possibly making a very good employee or partner unable to perform effectively. Fear has no place in leadership.

    The way we affect people in a lasting way is by our own character, and our understanding and use of emotion. We can order someone to do something, which may be part of the work day, or we can employ them at the emotional level, so they become fully devoted to the projects and provide some of their own motivation (积极性). Today's work place is all about relationships.

    Anyone works harder in a positive environment in which they're recognized and valued as a human being as well as a worker. Everyone produces just a bit more for someone they like Leaders understand the way things work. They know money is not the only most motivating factor in the work life of most people.

    The true strength of leadership is an inner strength that comes from the confidence of Emotional Intelligence—knowing your own emotions, and how to deal with them and those of others. Developing your emotional intelligence is the best thing you can do if you want to develop your relationships with people around you, which is the key to the leadership skills.