题干

以下几个实验现象,能说明声音产生的原因的是()

A:放在玻璃钟罩内的电铃正在发声,把钟罩内的空气抽去一些后,铃声明显减弱

B:把正在发声的收音机密封在塑料袋里,然后放入水中,人们仍能听到收音机发出的声音

C:拉小提琴时,琴弦的松紧程度不同,发出的声音也就不同

D:拨动吉它的琴弦发出声音时,放在弦上的小纸片会被琴弦弹开

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答案(点此获取答案解析)

D

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    In 1941, science fiction writer Isaac Asimov stated the Three Laws of Robotics. These laws come from the world of science fiction, but the real world is catching up. A law firm gave Pittsburgh's Carnegie Mellon University $10 million to explore artificial intelligence. Peter Kalis, chairman of the law firm, K&L Gates, said the development of technology had led to questions that were never taken seriously before. What will happen when you make robots that are smart, independent thinkers and then try to limit their freedom?

    Researcher Kalis said, “One expert said we'll be at a point when we give an instruction to our robot to go to work in the morning and it turns around and says, 'I'd rather go to the beach.'” He said that one day we would want laws to keep our free-thinking robots from running wild.

    With the law firm's gift, the university will be able to explore problems now appearing within automated industries. “Take driverless cars for example,” Kalis said. “If there's an accident concerned with a driverless car, what policies do we have in place? What kind of insurance policies do they have?” In fact, people can take a ride in a driverless car in Pittsburgh where an American online transportation network company uses the city as a testing ground for the company's driverless cars.

    The problems go beyond self-driving cars and robots. Think about the next generation of smartphones, those chips fixed in televisions, computers, fridges, etc., and the ever-expanding collection of personal data being stored in the “cloud”. So can Asimov's Three Laws of Robotics be used in reality? Is it necessary to have a moral guideline that everyone can understand? Whatever it is, doing no harm should be the very first one.