READING PASSAGE 1

You should spend about 20 minutes on Questions 1-12, which are based on Reading Passage 1 below.

HISTORY OF THE STEAM ENGINE

The first steam-powered machine was built in 1698 by the English military engineer Thomas Savery (c. 1650-1715). His invention, designed to pump water out of coal mines, was known as the Miner’s Friend. The machine, which had no moving parts, consisted of a simple boiler – a steam chamber whose valves were located on the surface – and a pipe leading to the water in the mine below. Water was heated in the boiler chamber until its steam filled the chamber, forcing out any remaining water or air. The valves were then closed and cold water was sprayed over the chamber. This chilled and condensed the steam inside to form a vacuum. When the valves were reopened, the vacuum sucked up the water from the mine, and the process could then be repeated.

A few years later, an English engineer named Thomas Newcomen (1663-1729) improved the steam pump. He increased efficiency by setting a moving piston inside a cylinder, a technique still in use today. A cylinder – a long, thin, closed chamber separate from the boiler – replaced the large, open boiler chamber. A piston – a sliding piece that fits in the cylinder – was used to create motion instead of a vacuum. Steam filled the cylinder from an open valve. When filled, the cylinder was sprayed with water, causing the steam inside to condense into water and create a partial vacuum. The pressure of the outside air then forced the piston down, producing a power stroke. The piston was connected to a beam, which was connected to a water pump at the bottom of the mine by a pump-rod. Through these connections, the movement of the piston caused the water pump to suck up the water.

The most important improvement in steam engine design was brought about by the Scottish engineer James Watt (1736-1819). He set out to improve the performance of Newcomen’s engine and by 1769 had arrived at the conclusion: if the steam were condensed separately from the cylinder, the cylinder could always be kept hot. That year he introduced the design of a steam engine that had a separate condenser and sealed cylinders. Since this kept the heating and cooling processes separate, his machine could work constantly, without any long pause at each cycle to reheat the cylinder. Watt’s refined steam engine design

used one-third less fuel than a comparable Newcomen engine.

Over the next 15 years, Watt continued to improve his engine and made three significant additions. He introduced the centrifugal governor, a device that could control steam output and engine speed. He made the engine double-acting by allowing steam to enter alternately on either side of the piston. This allowed the engine to work rapidly and deliver power on the downward and upward piston stroke. Most important, he attached a flywheel to the engine.

Flywheels allow the engine to run more smoothly by creating a more constant load, and they convert the conventional back-and-forth power stroke into a circular (rotary) motion that can be adapted more readily to power machinery. By 1790, Watt’s improved steam engine offered a powerful, reliable power source that could be located almost anywhere. It was used to pump bellows for blast furnaces, to power huge hammers for shaping and strengthening forged metals, and to turn machinery at textile mills. More than anything, it was Watt’s steam engine that speeded up the Industrial Revolution both in England and the rest of the world.

Steam was successfully adapted to powerboats in 1802 and railways in 1829. Later, some of the first automobiles were powered by steam. In the 1880s, the English engineer Charles A. Parsons (1854-1931) produced the first steam turbine, a new steam technology that was more efficient and which enabled the steam engine to evolve into a highly sophisticated and powerful engine that propelled huge ships and ran turbogenerators that supplied electricity.

READING PASSAGE 2  

You should spend about 20 minutes on Questions 13-26, which are based on Reading Passage 2 below:

A NEUROSCIENTIST REVEALS HOW TO THINK DIFFERENTLY

In the last decade a revolution has occurred in the way that scientists think about the brain. We now know that the decisions humans make can be traced to the firing patterns of neurons in specific parts of the brain. These discoveries have led to the field known as neuroeconomics, which studies the brain’s secrets to success in an economic environment that demands innovation and being able to do things differently from competitors. A brain that can do this is an iconoclastic one. Briefly, an iconoclast is a person who does something that others say can’t be done.

This definition implies that iconoclasts are different from other people, but more precisely, it is their brains that are different in three distinct ways: perception, fear response, and social intelligence. Each of these three functions utilizes a different circuit in the brain. Naysayers might suggest that the brain is irrelevant, that thinking in an original, even revolutionary, way is more a matter of personality than brain function. But the field of neuroeconomics was born out of the realization that the physical workings of the brain place limitations on the way we make decisions. By understanding these constraints, we begin to understand why some people march to a different drumbeat.

The first thing to realize is that the brain suffers from limited resources. It has a fixed energy budget, about the same as a 40 watt light bulb, so it has evolved to work as efficiently as possible. This is where most people are impeded from being an iconoclast. For example, when confronted with information streaming from the eyes, the brain will interpret this information in the quickest way possible. Thus it will draw on both past experience and any other source of information, such as what other people say, to make sense of what it is seeing. This happens all the time. The brain takes shortcuts that work so well we are hardly ever aware of them. We think our perceptions of the world are real, but they are only biological and electrical rumblings. Perception is not simply a product of what your eyes or ears transmit to your brain. More than the physical reality of photons or sound waves, perception is a product of the brain.

Perception is central to iconoclasm. Iconoclasts see things differently to other people. Their brains do not fall into efficiency pitfalls as much as the average person’s brain. Iconoclasts, either because they were born that way or through learning, have found ways to work around the perceptual shortcuts that plague most people. Perception is not something that is hardwired into the brain. It is a learned process, which is both a curse and an opportunity for change. The brain faces the fundamental problem of interpreting physical stimuli from the senses. Everything the brain sees, hears, or touches has multiple interpretations. The one that is ultimately chosen is simply the brain’s best theory. In technical terms, these conjectures have their basis in the statistical likelihood of one interpretation over another and are heavily influenced by past experience and, importantly for potential iconoclasts, what other people say.

The best way to see things differently to other people is to bombard the brain with things it has never encountered before. Novelty releases the perceptual process from the chains of past experience and forces the brain to make new judgments. Successful iconoclasts have an extraordinary willingness to be exposed to what is fresh and different. Observation of iconoclasts shows that they embrace novelty while most people avoid things that are different.

The problem with novelty, however, is that it tends to trigger the brain’s fear system. Fear is a major impediment to thinking like an iconoclast and stops the average person in his tracks. There are many types of fear, but the two that inhibit iconoclastic thinking and people generally find difficult to deal with are fear of uncertainty and fear of public ridicule. These may seem like trivial phobias. But fear of public speaking, which everyone must do from time to time, afflicts one-third of the population. This makes it too common to be considered a mental disorder. It is simply a common variant of human nature, one which iconoclasts do not let inhibit their reactions.

Finally, to be successful iconoclasts, individuals must sell their ideas to other people. This is where social intelligence comes in. Social intelligence is the ability to understand and manage people in a business setting. In the last decade there has been an explosion of knowledge about the social brain and how the brain works when groups coordinate decision making. Neuroscience has revealed which brain circuits are responsible for functions like understanding what other people think, empathy, fairness, and social identity. These brain regions play key roles in whether people convince others of their ideas. Perception is important in social cognition too. The perception of someone’s enthusiasm, or reputation, can make or break a deal. Understanding how perception becomes intertwined with social decision making shows why successful iconoclasts are so rare.

Iconoclasts create new opportunities in every area from artistic expression to technology to business. They supply creativity and innovation not easily accomplished by committees. Rules aren’t important to them. Iconoclasts face alienation and failure, but can also be a major asset to any organization. It is crucial for success in any field to understand how the iconoclastic mind works.

Once the dominant power source, steam engines eventually declined in popularity as other power sources became available. Although there were more than 60,000 steam cars made in the United States between 1897 and 1927, the steam engine eventually gave way to the internal combustion engine as a power source for vehicles.

READING PASSAGE 3

You should spend about 20 minutes on Questions 27-40, which are based on Reading Passage 3 below.

WILLIAM KAMKWAMBA

In 2002, William Kamkwamba had to drop out of school, as his father, a maize and tobacco farmer, could no longer afford his school fees. But despite this setback, William was determined to get his education. He began visiting a local library that had just opened in his old primary school, where he discovered a tattered science book. With only a rudimentary grasp of English, he taught himself basic physics – mainly by studying photos and diagrams. Another book he found there featured windmills on the cover and inspired him to try and build his own.

He started by constructing a small model. Then, with the help of a cousin and friend, he spent many weeks searching scrap yards and found old tractor fans, shock absorbers, plastic pipe and bicycle parts, which he used to build the real thing.

For windmill blades, William cut some bath pipe in two lengthwise, then heated the pieces over hot coals to press the curled edges flat. To bore holes into the blades, he stuck a nail through half a corncob, heated the metal red and twisted it through the blades. It took three hours to repeatedly heat the nail and bore the holes. He attached the blades to a tractor fan using proper nuts and bolts and then to the back axle of a bicycle. Electricity was generated through the bicycle dynamo. When the wind blew the blades, the bike chain spun the bike wheel, which charged the dynamo and sent a current through wire to his house.

What he had built was a crude machine that produced 12 volts and powered four lights. When it was all done, the windmill’s wingspan measured more than eight feet and sat on top of a rickety tower 15 feet tall that swayed violently in strong gales. He eventually replaced the tower with a sturdier one that stands 39 feet, and built a second machine that watered a family garden.

The windmill brought William Kamkwamba instant local fame, but despite his accomplishment, he was still unable to return to school. However, news of his magetsi a mphepo – electric wind – spread beyond Malawi, and eventually things began to change. An education official, who had heard news of the windmill, came to visit his village and was amazed to learn that William had been out of school for five years. He arranged for him to attend secondary school at the government’s expense and brought journalists to the farm to see the windmill. Then a story published in the Malawi Daily Mail caught the attention of bloggers, which in turn caught the attention of organisers for the Technology Entertainment and Design conference.

In 2007, William spoke at the TED Global conference in Tanzania and got a standing ovation. Businessmen stepped forward with offers to fund his education and projects, and with money donated by them, he was able to put his cousin and several friends back into school and pay for some medical needs of his family. With the donation, he also drilled a borehole for a well and water pump in his village and installed drip irrigation in his father’s fields.

The water pump has allowed his family to expand its crops. They have abandoned tobacco and now grow maize, beans, soybeans, potatoes and peanuts. The windmills have also brought big lifestyle and health changes to the other villagers. ‘The village has changed a lot,’ William says. ‘Now, the time that they would have spent going to fetch water, they are using for doing other things. And also the water they are drinking is clean water, so there is less disease.’ The villagers have also stopped using kerosene and can use the money previously spent on fuel to buy other things.

William Kamkwamba’s example has inspired other children in the village to pursue science. William says they now see that if they put their mind to something, they can achieve it. ‘It has changed the way people think,’ he says.