GRE Reading Comprehension
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Source: NO4
It is a popular misconception that nuclear fusion power is free of radioactivity; in fact, the deuterium-tritium reaction that nuclear scientists are currently exploring with such zeal produces both alpha particles and neutrons, (The neutrons are used to produce tritium from a lithium blanket surrounding the reactor.) Another common misconception is that nuclear fusion power is a virtually unlimited source of energy because of the enormous quantity of deuterium in the sea. Actually, its limits are set by the amount of available lithium, which is about as plentiful as uranium in the Earth's crust. Research should certainly continue on controlled nuclear fusion,but no energy program should be premised on its existence until it has proven practical. For the immediate future, we must continue to use hydroelectric power, nuclear fission, and fossil fuels to meet our energy needs. The energy sources already in major use are in major use for good reason.
The passage provides information that would answer which of the following questions?
- A What is likely to be the principal source of deuterium for nuclear fusion power?
- B How much incidental radiation is produced in the deuterium-tritium fusion reaction?
- C Why are scientists exploring the deuterium-tritium fusion reaction with such zeal?
- D Why must the tritium for nuclear fusion be synthesized from lithium?
- E Why does the deuterium-tritium reaction yield both alpha particles and neutrons?