Read the passage and choose the most suitable heading for paragraphs A-F from the list. There are two extra headings.
A) Nuclear power is currently produced by fission or splitting of atoms. This method produces dangerous by-products which are difficult to dispose of, and there is the possibility of radioactive fallout as in the Chernobyl disaster of 1986. Fusion, on the other hand, is a relatively safe process which does not rely on dangerous fuels.
B) Most people have heard of Einstein's formula, E=mc, but what does it mean? In fact, it is a description of how mass is converted into energy, and it is this energy which powers the stars, including our own sun. If we can reproduce this process on earth, we will have an infinite source of energy which does not rely on fossil fuels such as coal, gas or oil. One source of fuel for nuclear fusion is deuterium, which is a type of hydrogen found in ordinary water.
C) Conventional ways of generating power are wasteful.Typically, 60-90% of the energy generated is lost, meaning that we can only use 10-40%. There is also the problem of waste materials and pollution. Nuclear fusion is more than ten million times more efficient than burning coal as a source of energy.
D) The main difficulty in recreating the process of fusion on earth is the enormously high temperature which must be generated Fusion occurs naturally in the sun, which is at a
emperature of ten million K. This temperature must then be maintained long enough for the reaction to take place.
E) The first machine to reach the required temperature was the Tokamak, which was developed by Russian scientists in 1968. The Tokamak is a doughnut-shaped chamber surrounded by magnets, which create a strong electric current. The Tokamak could only maintain this temperature
for a few milliseconds, but this was the first time it had been achieved. Scientists are now working with lasers to increase the temperature.
F) It seems that it may be only a matter of time before we are able to produce enough power for all our needs, from a plentiful source, without causing damage to the planet. If so, imagine the benefits it would bring.
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