You should spend about 20 minutes on Questions 1–13, which are based on Reading Passage 1 below.
Meteor Strikes
On 15 February 2013, just after dawn, the sleepy Russian city of Chelyabinsk was woken by the biggest meteor strike on Earth in over 100 years. Several people videoed the meteor as it crashed through Earth’s atmosphere, passing close above the city and giving scientists vital clues as to where it had come from and how it had travelled to Earth. To the people of Chelyabinsk, the meteor shone 30 times brighter than the sun and had 20–30 times more energy than the atomic bomb dropped on Hiroshima. The meteor did not hit the ground, but due to its enormous speed exploded 29.7 kilometres above the ground, producing a bright flash, a cloud of hot dust and gas, many smaller fragments of meteor and a powerful shockwave. The latter was so strong that it knocked people off their feet and blew out the windows of homes, shops and factories. 1,500 people went to hospital with injuries indirectly caused by the strike, but matters could have been far worse if the meteor had made contact with the Earth.
The meteor was not an uncommon rock. From studying videos of the meteor's flight, scientists have concluded that it originated in the asteroid belt located between the orbits of Mars and Jupiter. At the time it entered Earth’s atmosphere, it weighed between 12,000 and 13,000 metric tonnes and was 10 metres in diameter. It crashed through the upper atmosphere at around 19 kilometres a second – above 50 times the speed of sound, fracturing at an altitude of between 45 and 50 kilometres. Such events happen on average every 10 or so years, mainly over oceans or unpopulated areas. This time the strike was over a city and observed by many people, reminding us how common these occurrences are.
A meteor strike has several phases. Moving through space, a meteor’s temperature can be around –100°C. It travels around 5 kilometres per second until Earth’s gravity accelerates it to 17 kilometres a second. It begins to encounter the atmosphere 140 kilometres above the Earth but there is little air resistance until about three seconds later, when it reaches 100 kilometres above the ground. At this point the air becomes dense, causing the meteor to glow as the material on its surface melts. The mix of burning gas and dust creates a fireball as the meteor loses 3 to 6 millimetres of surface mass per second as it is heated to over 1,800°C. The rate of loss of material through heat is so rapid that the core temperature of the meteor is still very low while at the same time a tail of vaporised dust and gas becomes visible. These tails can often be seen for up to 45 minutes and may be followed by a sonic boom as the meteor crashes through the sound barrier. During its flight to the Earth, the meteor slows down by 70 per cent and it is during this period that it may fracture and split. At this point some meteors explode in a violent airburst while others enter dark flight – the period when the meteor slows down so much that it stops burning and it falls to the ground as a cold rock.
The Chelyabinsk airburst left only a few large pieces of the meteor: one rock was recovered near the town of Timiryazevskiy, another fell on a house in Deputatskiy, and the largest piece was found by divers at the bottom of Lake Chebarkul. The meteor was the largest to crash to Earth since 1908, when a meteor exploded over an area near the Tunguska River in Siberia. Although information about the event is scarce, the theory most scientists share is that an asteroid around 36.5 metres in diameter and travelling at 54,000 kilometres per hour entered the atmosphere above Russia. It exploded in an airburst at 28,000 feet, releasing energy equal to about 185 Hiroshima atomic bombs and flattening trees across an area of 800 square miles. Airbursts the size of Tunguska are estimated to occur every 1,200 years on average. But following the Chelyabinsk meteor, scientists now think the risk of similar objects hitting our planet may be ten times greater than thought previously.
You should spend about 20 minutes on Questions 14–26, which are based on Reading Passage 2 below.
Reading Passage 2
Some years ago, in 2009, the Mayor of London's advisor on waste questioned the efficiency of recycling, making environmentalists very angry. The chief executive of the independent not-for-profit company Waste and Resources Action Programme (WRAP), Dr Liz Goodwin, responded, saying that the advisor's comments were unhelpful to recycling initiatives and that 'WRAP's independent research, carried out by internationally recognised experts, has shown that across the board recycling is the best environmental option'. Dr Goodwin went on to say: 'Around two thirds of households now recycle as a way of life. The message to householders is that recycling is delivering great environmental benefits and there is absolutely no reason for them to stop.'
However, others can see several reasons to stop recycling, calling the UK's recycling schemes a disorganised waste of time. At the moment recycling means ordinary people sorting out their own waste when it could be dealt with more economically, more efficiently and in a more environmentally friendly way. In the past 20 years in the UK, people have accepted their work as unpaid labourers for councils and waste recycling companies. Every week millions of households diligently sort out their plastic bottles from their glass bottles, their cardboard from their paper, and put it into the correct container. The type and colour of container varies significantly throughout the country; in parts of Scotland you can't recycle aluminium foil but in the south of England the council positively want it. This may seem like a small matter, but it does point to the lack of a coherent strategy for waste disposal. The Chartered Institution of Wastes Management certainly thinks that Britain doesn't have a national strategy. More importantly, if we could count the number of hours spent sorting out recyclable waste – 45 minutes each week by one estimate – and then multiply it by the number of households – 24 million – we get a massive 18 million hours spent each week on recycling.
Other places, however, do things differently. In Maryland, USA, a high-tech system for sorting out waste in a plant and recycling it afterwards increased recycling use by 30 per cent, probably because people did not need to spend three quarters of an hour every week sorting out the waste. There are other issues caused by asking people to give their free time to sort out waste. Because most people generally do not want to do this, local authorities have introduced a range of punishments to deal with them. One is to decrease the regularity of waste collection; another is to check people's rubbish bins and fine them if they put the wrong waste in the wrong bin. Putting paper in the wrong recycling bin cost a journalist from Wales £200.
One reason why questioning the efficiency of recycling makes environmentalists uneasy is that recycling may actually have the opposite effect on the environment. When Britain's waste has been collected, it is sent abroad – to Europe or even longer distances to China – for processing. The cost to the environment of transporting the waste around the world is considerable. But there are alternatives. Firstly, simply using less would help. Secondly, the waste could be buried again in landfill sites around the UK. According to Tim Worstall, in Britain we 'dig up some 110 million cubic metres (mcm) of sand, gravel and clay every year; and each year we produce some 100 mcm of waste'. Unfortunately, the European Union is discouraging landfill by fining countries in the EU who landfill too much. The next alternative is incineration – burning the waste to produce energy. Naturally, incineration is controversial, but burning plastic bottles in power stations to generate electricity saves using fossil fuels like gas, oil and coal. Waste heat produced by the process can be distributed to local public buildings and nearby homes. The question is, which is better environmentally: transporting the waste across the world, or using it locally to produce energy?
Recycling is not a new concept: we have done it for years. We have recycled old cars, scrap metal and paper for a long time now. However, the difference between then and now is that we used to recycle when it made economic sense. Today, it is part of our law and it has somehow become a belief that recycling is the only right thing to do whereas there may be better and more environmentally friendly alternatives. Recycling is not the only answer and the discussion should continue.
You should spend about 20 minutes on Questions 27–40, which are based on Reading Passage 3 below.
Hello 3D printing, goodbye China
A A spectre is haunting the great container ship ports of China, with their highways jammed by lorries and the vast factory estates stretching from the coast of the South China Sea to the mountainous inland provinces. It is the spectre of a revolution led by a quiet, software-driven 3D printer, a machine that can laser up layers of liquid or granular resin or even cell tissue into a finished product. Some 3D printers are huge devices that make complete components such as aircraft parts. Others are small units that could stand next to a desk and create a small plastic prototype. Maplin, the British electronics retailer, said last week it would start selling one for just £700. The Velleman K8200 will allow those who are so inclined to make simple objects — mobile phone covers, perhaps, or toys. 'The only restriction is your imagination. You can make whatever you want,' said Pieter Nartus, export manager at Velleman.
B To visionaries in the West, the digital 3D printer promises to disrupt conventional manufacturing and supply chains so radically that advocates compare its impact to the advent of the production line or the internet. In China, whose big factories are thinking of using giant 3D printers for manufacturing, the technology does not seem to pose an immediate threat. 'It is on their horizon but it is not a factor right now,' says a British buying agent who sources plastics in China. However, as Chinese leaders ought to know from their compulsory classes in Karl Marx, control of the means of production is everything. And if 3D printing takes off, production will come back to a place near you.
C The implications, economists say, are limitless. No huge factories. No fleets of trucks. No ships. No supply chain. No tariffs. Few middlemen. Orders tailored exactly to demand, so no need for stock and warehouses. Just a printer, raw materials, software and a design. The advantages do not end there. Because the item is 'sintered' – created from a powdered material – to precise settings using a laser, there is no waste such as metal shavings. To customise a product, the user simply changes the software. An operator presses a button and the printer spits out the item.
D 'The first implication is that more goods will be manufactured at or closer to their point of purchase or consumption,' said Richard D'Aveni, a professor at Dartmouth College in the USA. Writing in the Harvard Business Review, D'Aveni predicted the elimination of the long supply chain linked to a huge factory staffed by cheap workers and sited on the other side of the world. It may be the most significant, if underplayed, article in that distinguished publication in decades. 'China has grabbed outsourced manufacturing contracts from every mature economy by pushing the mass-manufacturing model to its limit,' he wrote. 'It not only aggregates enough demand to create unprecedented efficiencies of scale but also minimises a key cost: labour. ... Under a model of widely distributed, highly flexible small-scale manufacturing, these daunting advantages become liabilities. No workforce can be paid little enough to make up for the costs of shipping across oceans.'
E In the brutal war for margin amid volatile commodities and currencies at the bottom end of the market, where China has carved its niche, the numbers tell their own ominous story. In a world of 3D manufacturing, the classic supply chain makes no commercial sense. 'China won't be a loser in the new era,' D'Aveni argued in the Harvard Business Review. 'It will have a domestic market to serve . . . and its domestic market is huge. But China will have to give up on being the mass-manufacturing powerhouse of the world.'
F China, of course, is not sitting still. It is eagerly buying Western 3D printing technology and making its own lightweight machines to sell to consumers. The Ministry of Industry and Information Technology has already allocated £20 million to fund 10 research centres and set up a group of 40 participating companies. So there is no doubt about China's scientific, engineering and intellectual commitment to 3D manufacturing. However, it is a fundamentally different concept in China. To the Chinese, it is an industrial tool to be used in making more things to sell. To Western economies that are hooked on cheap imports with a huge carbon footprint, it could be a means of transformation – perhaps even an agent of de-industrialisation.