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Read the article and for questions 61-70, choose from the sections (A-E). The sections may be chosen more than once.
In which section is the following mentioned?
61. an instance in which an individual felt averse to divulge certain information
62. the potential of a means of transport to carry cargo at high speeds
63. the necessity to overhaul contemporary transit systems
64. an instance in which an individual underestimated the potential of a technology
65. a means of transport which has recently been put to public use
66. a collaborative effort at developing rapid transit technology
67. the view that contemporary transports systems are underdeveloped
68. uncertainty as to whether funds will be available to finance a project
69. the potential of a technology to surpass conventional expectations
70. the extent to which a proposed transit system could reduce ecological damage
Vacuum Trains: Space-Age Travel on Earth
Vacuum trains work on a very simple principle of physics, namely, it's easier to move an object through a vacuum than it is through a medium, such as air. Are vacuum trains the future of travel?
A. When compared to the many other scientific and technological advances of the late 20th and early 21st centuries, it could be said that little progress has been made in the field of mass transit systems. But for Concorde, the turbo-jet powered airplane which retired due to budgetary concerns in 2003, and the bullet trains of Japan, little has changed in the way that groups of people travel to far-off destinations. By and large, we still use the same transport technologies and travel at the same speeds to those of fifty years ago. In times of scientific and technological sluggishness, it's often best to permit 'blue-sky' thinkers to take the stage. One such individual whose creative thinking was not limited by current wisdom or beliefs was the American physicist Robert H. Goddard (1882-1945). Known as the father of modern rocket propulsion, Goddard was often mocked during his lifetime for the seemingly pie-inthe-sky nature of his proposals. The ridicule caused Goddard to become increasingly reticent about the nature of his work over the course of his career; so much so that many of his designs did not come to light until after his death. Among Goddard's revolutionary ideas was one for a high-speed train known as vacuum tube train, or ‘vactrain' for short.
B. The central rationale behind a vactrain as conceived by Goddard in the 1910s, is that trains could travel considerably faster and use up appreciably less energy if they were not held back by air resistance. A conventional train pushes a wall of air ahead of it and in doing so causes an area of low pressure to form behind it. Both these phenomena end up 'pulling the train back and necessitate huge amounts of energy to be expended in order to counteract the forces. But by placing a train line within a sealed tunnel and voiding the tunnel of all air (i.e. creating a vacuum) this rolling resistance is nullified. The sealed tunnel can be placed above ground or even in underground bored rock the latter hypothetically enabling cross-oceanic travel at speeds once thought the sole domain of science fiction. Such technology has the potential to unequivocally supplant the aircraft as the world's fastest mode of mass transit. Goddard's early designs, for instance, proposed the possibility of travelling from Boston to New York in just 12 minutes at speeds averaging around 1,000 mph (1,600 km/h). In actual fact, by combining vactrain technology with another form of technology known as maglev, such trains could travel a great deal faster.
C. Maglev (short for magnetic levitation) trains are trains that float on a bed of magnets thus negating the recurrent friction that conventional trains experience from running on tracks using mechanical apparatuses such as wheels, axles and bearings. By causing the train to, in effect, fly along its route, albeit just inches from the surface of a magnetic line, maglev trains can travel at speeds of up to 361 mph (581 km/h). Maglev trains are currently operational (albeit in small numbers) in Japan, Korea and China. Although still a nascent venture, they have not as yet proved to merit any undue concerns in terms of safety. But what if a maglev train was placed within a vacuum? Some believe such trains could reach speeds of more than 4,000 km/h, allowing passengers to travel from Europe to North America in under an hour.
D. Certainly, much interest has been shown by scientists and innovators eager to cash in on the ‘next big thing’. Indeed, several patents have already been taken out proposing various uses for the merger of vactrain and maglev technologies. One scientist in the front line of such research is American engineer, Daryl Oster, who holds a patent for what he calls ‘Evacuated Tube Transport (ETT). Oster's proposes using relatively small six-person automated capsules that could travel up to 4,000 km/h on maglev lines within vacuumed tunnels. His research has piqued the interest of the Chinese government who acquired a license to use ETT technology in combination with their own pre-existent maglev research. According to Oster, the world could be using ETT for world travel within the next 10 years.
E. So is ETT really a feasible transportation technology for the future? Some put paid to the idea because of its prohibitive cost. For instance a hypothetical underground ETT line from Los Angeles to New York City would cost an estimated US$1 trillion, with an elevated surface level alternative only lessening the brunt of the cost by a third. Hence, the apathetic response most governments, bar the Chinese government perhaps, give to ETT proposals. But some futurologists point to the mother of all invention: necessity. The carbon footprint of current mass transit systems is considerable and must be reduced. Fossil fuels deposits are dwindling and energy-efficient alternatives will soon be required. Vactrains run entirely on electricity so there would be no carbon footprint whatsoever. Thus, while construction would be expensive, supporters of ETT technology emphasise the long-term cost-effectiveness of the venture - in terms of the environment, energy usage, and the economic advantages attainable by a world having a speedier mass transit infrastructure. Still , it remains to be seen who, if anyone, will take the plunge. ETT technology could well remain just a pipe dream.
In which section is the following mentioned?
61. an instance in which an individual felt averse to divulge certain information
62. the potential of a means of transport to carry cargo at high speeds
63. the necessity to overhaul contemporary transit systems
64. an instance in which an individual underestimated the potential of a technology
65. a means of transport which has recently been put to public use
66. a collaborative effort at developing rapid transit technology
67. the view that contemporary transports systems are underdeveloped
68. uncertainty as to whether funds will be available to finance a project
69. the potential of a technology to surpass conventional expectations
70. the extent to which a proposed transit system could reduce ecological damage
Vacuum Trains: Space-Age Travel on Earth
Vacuum trains work on a very simple principle of physics, namely, it's easier to move an object through a vacuum than it is through a medium, such as air. Are vacuum trains the future of travel?
A. When compared to the many other scientific and technological advances of the late 20th and early 21st centuries, it could be said that little progress has been made in the field of mass transit systems. But for Concorde, the turbo-jet powered airplane which retired due to budgetary concerns in 2003, and the bullet trains of Japan, little has changed in the way that groups of people travel to far-off destinations. By and large, we still use the same transport technologies and travel at the same speeds to those of fifty years ago. In times of scientific and technological sluggishness, it's often best to permit 'blue-sky' thinkers to take the stage. One such individual whose creative thinking was not limited by current wisdom or beliefs was the American physicist Robert H. Goddard (1882-1945). Known as the father of modern rocket propulsion, Goddard was often mocked during his lifetime for the seemingly pie-inthe-sky nature of his proposals. The ridicule caused Goddard to become increasingly reticent about the nature of his work over the course of his career; so much so that many of his designs did not come to light until after his death. Among Goddard's revolutionary ideas was one for a high-speed train known as vacuum tube train, or ‘vactrain' for short.
B. The central rationale behind a vactrain as conceived by Goddard in the 1910s, is that trains could travel considerably faster and use up appreciably less energy if they were not held back by air resistance. A conventional train pushes a wall of air ahead of it and in doing so causes an area of low pressure to form behind it. Both these phenomena end up 'pulling the train back and necessitate huge amounts of energy to be expended in order to counteract the forces. But by placing a train line within a sealed tunnel and voiding the tunnel of all air (i.e. creating a vacuum) this rolling resistance is nullified. The sealed tunnel can be placed above ground or even in underground bored rock the latter hypothetically enabling cross-oceanic travel at speeds once thought the sole domain of science fiction. Such technology has the potential to unequivocally supplant the aircraft as the world's fastest mode of mass transit. Goddard's early designs, for instance, proposed the possibility of travelling from Boston to New York in just 12 minutes at speeds averaging around 1,000 mph (1,600 km/h). In actual fact, by combining vactrain technology with another form of technology known as maglev, such trains could travel a great deal faster.
C. Maglev (short for magnetic levitation) trains are trains that float on a bed of magnets thus negating the recurrent friction that conventional trains experience from running on tracks using mechanical apparatuses such as wheels, axles and bearings. By causing the train to, in effect, fly along its route, albeit just inches from the surface of a magnetic line, maglev trains can travel at speeds of up to 361 mph (581 km/h). Maglev trains are currently operational (albeit in small numbers) in Japan, Korea and China. Although still a nascent venture, they have not as yet proved to merit any undue concerns in terms of safety. But what if a maglev train was placed within a vacuum? Some believe such trains could reach speeds of more than 4,000 km/h, allowing passengers to travel from Europe to North America in under an hour.
D. Certainly, much interest has been shown by scientists and innovators eager to cash in on the ‘next big thing’. Indeed, several patents have already been taken out proposing various uses for the merger of vactrain and maglev technologies. One scientist in the front line of such research is American engineer, Daryl Oster, who holds a patent for what he calls ‘Evacuated Tube Transport (ETT). Oster's proposes using relatively small six-person automated capsules that could travel up to 4,000 km/h on maglev lines within vacuumed tunnels. His research has piqued the interest of the Chinese government who acquired a license to use ETT technology in combination with their own pre-existent maglev research. According to Oster, the world could be using ETT for world travel within the next 10 years.
E. So is ETT really a feasible transportation technology for the future? Some put paid to the idea because of its prohibitive cost. For instance a hypothetical underground ETT line from Los Angeles to New York City would cost an estimated US$1 trillion, with an elevated surface level alternative only lessening the brunt of the cost by a third. Hence, the apathetic response most governments, bar the Chinese government perhaps, give to ETT proposals. But some futurologists point to the mother of all invention: necessity. The carbon footprint of current mass transit systems is considerable and must be reduced. Fossil fuels deposits are dwindling and energy-efficient alternatives will soon be required. Vactrains run entirely on electricity so there would be no carbon footprint whatsoever. Thus, while construction would be expensive, supporters of ETT technology emphasise the long-term cost-effectiveness of the venture - in terms of the environment, energy usage, and the economic advantages attainable by a world having a speedier mass transit infrastructure. Still , it remains to be seen who, if anyone, will take the plunge. ETT technology could well remain just a pipe dream.
