问题 选择题

用绳子拉着重物在光滑水平面上运动,当重物速度达到v时,绳子突然断裂.绳子断裂后,重物的速度将(  )

A.逐渐减小

B.逐渐增大

C.立即变为零

D.保持v不变

答案

用绳子拉重物在光滑水平面上运动,当绳子突然断裂后,重物由于不再受力的作用,仍要保持原来的运动状态,所以重物的运动速度将保持v不发生变化.

所以选项A、B、C错误,D正确.

故选D.

单项选择题
填空题

[A] Look and listen and think about what the other person says, how they say it and what they do. Be aware of yourself as well If you recognize a pause in the wrong place or a phrasing that implies weakness then immediately look for a way to counter the impression produced. The game is not lost until the encounter is over. Many of these signals do not require a deep study of psychology. They require awareness, some common sense to recognize meaning and a readiness to do something about the signals that are sent and received.

[B] Recognition of body language also helps to understand our own feelings. If we feel irritated by someone, could it be because they are leaning back in their chair, with head slightly tilted back (looking down their noses at us), perhaps with hands together making a shape like a church steeple, or with hands behind their head We may both be standing up and the other person is holding their jacket lapels, waggling their thumbs at us. These are all gestures of superiority and might explain our annoyance. Understanding this, we may be able to handle it better.

[C] If we can interpret this involuntary commentary then our negotiating position will be per. We could recognize a lie, whether our arguments were being accepted or whether the other party was unreceptive and adjust our behaviour accordingly.

[D] Many studies claim to show that over 50 percent of the messages we convey are through gesture, expression and posture. This is in addition to the messages conveyed through tone of voice. Whether it be banging the table with our fists, directing an angry stare or looking puzzled, it is hard to deny the importance of this side of communication. The astute dealer is always alive to body language but don’t concentrate so much on it that you don’t pay attention to what is actually said.

[E] Signals don’t appear singly but in clusters of several that reinforce each other. Don’t rely upon just one gesture that may be misinterpreted but take the wider evidence available. We frequently say things we don’t mean and mean things we don’t say. How easy it is to imply things we don’t mean! Interpretation of the "sub-text" of communication is inaccurate. Don’t rely upon what you think is going on under the surface without checking you interpretation.

[F] Some expressions and gestures are particular to specific cultures, while others are common to the entire human race, such as smiling or the bared teeth of anger. A smile can be faked, it can mask anger and aggression. However, the way we stand and what we do with our hands is harder to control. There is another layer of body signals, of greater subtlety, such as the narrowing of eyes, the shape of the smile and even the contraction of the pupils of the eye, which may also betray the real feelings of the smiling negotiator. Most of those gestures are universal.

[G] Typically, someone who is lying will avoid your eye and may look downwards. They may touch their faces around the mouth and have the palms of their hands hidden from you. The other party may adopt a tone of voice of great sincerity and look you steadily in the eye in order to reinforce the deception of their words. If you look away from that gaze you may see signals they are unable to control, which give the game away.

[H] We all recognize a lot unconsciously, which is how we get a feeling that someone is lying or that they are bored. In lying, people’s expressions, postures and gestures convey contrary messages to their words and we intuitively recognize the disparity. To negotiate more effectively, be sensitive to these signals, whether by paying more attention to your feelings or by consciously observing and thinking about the gestures and expressions we see.

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