新编英语教程第三册Unit06(在线收听

Unit 6

TEXT I

Atomic Cars

Text

Every motorist dreams of a car of the future that does not have to be refuelled every few hundred miles, a car that will cost little to run because there is no outlay on petrol.
"Of course," you hear it said by an optimistic motorist, "the answer is the atom. Harness atomic power in a car, and you'll have no more worries about petrol. The thing will run for years without a refill."
And, theoretically, he is right. The answer is the atom. If atomic power could be used in a car, one small piece of uranium would keep the engine running for twenty or more years. Of course, this would cut the cost of running a car by quite a few hundred pounds, depending upon how much you spend on petrol.
But is this science-fiction-like picture of the atom exploding peacefully beneath the bonnet of a car possible? In theory it is, since already the atom has been harnessed to drive submarines, and an atomic engine is already in existence. But, say the experts, there are many problems still to be conquered before such an engine can in fact be fixed into a car.
Now what exactly are these problems that stand between you and a car that you will never have to refuel? Frankly, most of them can be summed up in one word — radiation. An atomic reactor, the kind of engine that would produce energy by atom-splitting, throws off radiation, extremely dangerous radiation. These rays are just as dangerous as when they are released from an atomic bomb. This radiation penetrates anything except the thickest concrete and lead, with fatal results for anybody in its path. Thus, at the moment any car carrying an atomic engine would also have to carry many tons of lead in order to prevent the radiation from escaping.
Since a car made up of tons of lead is rather impracticable, the only answer at the moment seems to be the discovery or invention of a metal that will be strong enough to hold in the rays, but at the same time light enough for a vehicle to carry with ease and economy. Most likely this metal would have to be synthetic, since no natural metal except lead has yet proved fit for the job. When this light metal is invented, the motoring world will be well on the way to an atomic car. However, even after the invention of a protective but light metal, two other problems still remain, those of economics and safety.
It is extremely doubtful whether at the beginning a really economic engine could be made, that is, one cheap enough to make it worth putting in a car. But it seems safe to say that eventually, as techniques and mass production come in atomic engines, the price will go down. This is basic economics, and manufacturers should eventually be able to produce something that will at least be cheaper than having to pay for petrol during the lifetime of the car.
But then this third problem still remains, that of safety. Suppose that there is a road accident involving one, or perhaps two, atomic cars, and that the atomic reactor or its protective covering were damaged. Any explosion would be equal to that of a very small atomic bomb. The effects of such an explosion would be felt for several miles around. As will be realized, this is perhaps the biggest problem of all to overcome. Is it possible to make an atomic engine that will be really safe in every circumstance?
From an article in Ford Times

TEXT II

Energy or Extinction?

Energy or Extinction is the title of Professor Sir Fred Hoyle's latest book. I've met Fred Hoyle and I know he means what he says — and what he says in this book is riveting. Generally I am unimpressed by Doom-sayers. Their arguments tend to be sloppy, their facts chosen to alarm and not to inform Fred Hoyle is in a different league. He is a scientist who lays out the components of his case so clearly that even someone like myself, who abandoned physics in a panic at 14, can just about grasp his meaning.
More importantly, Fred Hoyle is full of common sense. When you are reading something as urgent and important as Energy or Extinction it is no small thing to be reassured that the author is a Yorkshireman and a man who, you feel, from the prose and from the honesty of his attitudes, you would trust on this and many other matters.
I went to see him at his home in Cumbria. Ironically he lives just a few miles from the nuclear power complex at Windscale which large bodies of opinion would like to close down, although he regards nuclear power as the only hope for a peaceful and technologically civilized future.
"I think the way we're heading is towards a world where people are going to go cold and hungry," he said, "and where increasingly large populations are going to start fighting for the diminishing resources. If people are going that way out of ignorance, because they are badly informed, then I think it my duty to set the facts before them."
He ran through the facts briskly. At the present rate of usage, oil will last for no more than 40 years, while coal could last 300 years. But if the underdeveloped nations begin to claim the standard of living we ourselves enjoy, then the lifespan of oil and coal will shorten dramatically. In either case, we are quite definitely running out, and to maintain the civilization and services we have built up demands new energy resources urgently and on a massive scale. The only hope, as Hoyle sees it, lies in nuclear energy.
Why then, I asked, was there so much opposition to the development of nuclear reactors? "The great majority of people are well meaning, but what they are really doing is to displace a fear of nuclear war into a fear of nuclear energy. What they do not seem to realize is that they are bringing the thing they fear closer. Because if the coal and the oil supplies run down, the world's most powerful nations will start scrapping for what remains. These are the countries with the big nuclear arsenals, and nuclear war is not at all improbable once these countries get desperate. The one thing that will prevent this is plenty of energy."
He poured scorn on the idea that leaks from places such as Windscale could spread radioactivity among the population. "If these people campaigning at Windscale were serious, they would be pressing for the evacuation of the county of Cornwall, because people there live on rocks that give off a natural radioactivity."
"Everything is radioactive. These walls are radioactive, the floor is radioactive, and Cornwall has more of this than other parts of the country. They would also be pressing for the medical profession being refused permission to use X-rays. The risks I've taken in the five years I've lived in Cumbria, due to the presence of Windscale, are less than the risk I take in one journey from here to Keswick in my car."
By Melvin Bragg

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