What is controlled nuclear fusion?
• Controlled nuclear fusion is the attempt by scientists to extract energy by fusion reaction in the laboratory. Lacking the enormous pressure of the Sun”s core, how do laboratory experiments in controlled nuclear fusion manage to hold the very hot hydrogen together? • They use magnetic fields. The teacher may explain further: no magnetic field produced in the lab can match the enormous pressure at the center of the Sun. However, fusion is also possible at lower pressures and temperatures, with fuels that “fuse” more easily–for instance, heavy forms (“isotopes”) of hydrogen, which besides a proton contain one or two neutrons. Even with them, however, no commercially useful fusion power has as yet been released. If stars get their heat by the fusion of hydrogen to form helium–what happens when all the hydrogen is used up and converted to helium? (Teacher might explain) For a while the star may gain energy from the fusion of nuclei larger than hydrogen, but that energy source does not
