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如图所示是条形磁铁与通电螺线管之间的磁感线分布情况,请标出磁感应线的方向,并画出螺线管的绕线.

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同类题4

   A 10-year-old boy decided to learn judo though he had lost his left arm in a car accident. The boy was doing well, so he couldn't understand why, after three months of training, the master had taught him only one move.
   “ Master,” the boy finally asked, “shouldn't I be learning more moves?"“ This is the only move you know, but this is the only move you'll ever need to know,” the teacher answered.
   Several months later, the teacher took the boy to his first competition. Surprising himself, the boy easily won his first two matches. The third match proved to be more difficult, but after some time, his opponent (对手) became impatient and charged; the boy skillfully used his one move to win the match. Still amazed by his success, the boy was now in the final.
  This time, his opponent was bigger, stronger, and more experienced. Soon after the match started, the boy seemed to lose. Thinking that the boy might get hurt, the judge called a time-out. He was going to stop the match when the teacher appeared. “ No,” the teacher said, “Let him continue.” A short time after the match carried on, his opponent made a careless mistake. At once, the boy used his move to pin (压住) him. The boy won the match and the competition.
  On the way home, the boy asked the teacher what was really in his mind. " Why could I win the competition with only one move?" The teacher answered. "First, you've mastered one of the most difficult throws in judo. Second, your opponent can only attack your left arm to win you.”
根据短文内容完成下面的表格,每空一词。

Title: One’s weakness can become his____ 
A boy had lost left arm, ____  he decided to learn judo
After three months of training, the master taught him only one move.
His first____ First three matchesHe won.
FinalHis opponent was bigger, ____  and more ____ .
At the ____ , the boy seemed to lose the match.
The judge was____  that the boy might get hurt and called a time-out.
His opponent made a mistake. The boy used his move and pinned him.
He became the ____  of the match.
____ 1. He had almost mastered one of the most difficult throws in all of judo.
 The opponent can win the match by ____  your left arm.

同类题5

阅读理解

    When Carson Palmer, a professional American football player, hurt his arm a few years ago, he took a week off from throwing the football. But in his head, Palmer practiced every day. The following weekend, Palmer had the best game of his life.

    For more than a century, scientists have been trying to understand how this mental training works. In the 1930s, researchers proved by experiment that when you're imagining an action, your brain sends signals to your muscles(肌肉) which are too weak to tighten the muscles but might help train the body to perform. In other words, mental practice might create a pattern in your head, like an inner how-to guide for a particular skill.

    Sports psychologists have conducted hundreds of studies comparing imagined and physical practice for actions. On the whole, the research shows that mental training works. A 2012 study, for example, compared 32 amateur golfers who practiced hitting the balls to another 32 who merely held a golf club in their hands and visualized(想象)their swings. Under the same training rules, both groups improved their skills by getting the ball about 4 inches closer to the hole.

    Visualization has advantages over the real thing: You can do it anywhere, even when injured. It is safe-a major plus for high-risk performers such as gymnasts and surgeons. And you can practice for longer periods of time because you're not restricted by physical tiredness, That's not to say it's easy, we've had Olympic-level athletes sitting in our lab, visualizing the movements for two hours," says Tadhg Macintyre, a sports psychologist at the University of Limerick in Ireland. “When we're done, they're absolutely tired.”

    It doesn't work for everyone, though. "If you're a novice, the effect can be harmful,” warns Macintyre. If you're trying to visualize a free throw, and you don't even know the proper movement, then you're probably going to mentally practice the wrong skill.”