| 在职申硕英语考试易错题（2019/5/11） |
| 第1题：Experienced baseball fielders can tell how far a ball is going to travel just by listening to the crack of the bat. If they didn’t, they wouldn’t stand a chance of catching it, claims a physicist in New York. "When a baseball is hit straight at an outfielder, he cannot quickly judge the angle of the scent and the distance the ball will travel," says RobertAdair, a physicist at Yale University. If he relied purely upon visual information, the fielder would have to wait for about one-and-a-half seconds before he could tell accurately if the pitcher hit the ball long or short.By this time the ball may have travelled too far for him to reach it in time. To stand a fighting chance of catching it, according toAdair, fielders must listen to the sound the ball hitting the bat to judge how far it will travel. There is anecdotal evidence to support this, he says.A、former centre fielder toldAdair: "If I heard a crack I ran out, if I heard a clunk, I ran in." To test his hypothesis,Adair calculated how quickly a fielder could change direction if he had misjudged whether the ball was going long or short. The difference between the "crack" and "clunk” can he explained by how well the batter has hit the ball, and could mean a difference in running distance of as much as 30 metres, he told delegates at a meeting of theAcoustical Society ofAmerica inChicago last week. Scientists already knew that to hit a ball long the batter must strike it somewhere near the vibrational node of the bat, known as the sweet spot.Balls hit on the sweet spot generate fewer energy-sapping vibrations in the bat, allowing greater energy transfer to the ball.Conversely, mishit balls make the bat vibrate strongly and so do not travel as far. Adair is quick to point out that this only applies to wooden bats, which are used in major league baseball.Aluminum bats, on the other hand, tend to produce a fairly uniform "ping” sound regardless of where you hit them. Adair points out that his theory can’t be applied to aluminum bats because ______.A．the "ping” sound is too vague for a fielder to catch B、with the aluminum bats the batter always hits the ball stronger C．they don’ t produce different sounds of "crack" and "clunk" D．the sounds they produce may interfere with the fielder’s judgment |
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| 第2题：Most lecturers find it expedient to use notes when addressing to graduate students. A．troublesome B．expensive C．useful D．improper |
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| 第3题：The last mayor was assassinated when he was fifty years old. A．honored B．murdered C．elected D．impeached |
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| 第4题：The current emergency in MexicoCity that has taken over our lives is nothing I could ever have imagined for me or my children. We are living in an environmental crisis, an air-pollution emergency of unprecedented severity. What it really means is that just to breathe here is to play a dangerous game with your health. As parents, what terrorizes us most are reports that children are at higher risk because they breathe more times per minute. What more can we do to protect them and ourselves Our pediatrician’s (儿科医师的) medical recommendation was simple: abandon the city permanently. We are foreigners and we are among the small minority that can afford to leave. We are here because of my husband’s work. We are fascinated by Mexico--its history and rich culture. We know that for us, this is a temporary danger. However, we cannot stand for much longer the fear we feel for our boys. We cannot stop them from breathing. But for millions, there is no choice. Their lives, their jobs, their futures depend on being here. Thousands of Mexicans arrive each day in this city, desperate for economic opportunities. Thousands more are born here each day.Entire families work in the streets and practically live there. It is a familiar sight: as parents hawk goods at stoplights, their children play in the grassy highway dividers, breathing exhaust fumes. I feel guilty complaining about my personal situation; we won’t be here long enough for our children to form the impression that skies are colored only gray. And yet the government cannot do what it must to end this problem. For any country, especially a developing Third World economy like Mexico’s, the idea of barring from the capital city enough cars, closing enough factories and spending the necessary billions on public transportation is simply not an option. So when things get bad, as in the current emergency, Mexico takes half measures--prohibiting some more cars from circulating, stopping some factories from producing--that even its own officials concede aren’t adequate. The word "emergency" implies the unusual.But when daffy life itself is an emergency, the concept loses its meaning. It is human nature to try to adapt to that which we cannot change, or to mislead ourselves into believing we can adapt. The Mexican government takes half measures to solve the pollution problem because______A．Mexican economy depends very much on cars and factories B．it is not wise enough to come up with effective measures C．Mexicans are able to adapt themselves to the current emergency D．Mexicans enjoy playing dangerous games with their health |
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| 第5题：一维、无内热源、导热系数为常数的无限大平板稳态导热，平板左侧面绝热，右侧面温度为50℃。请问平板左侧面和中间截面的温度各为多少？为什么？ |
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