The fusion of two deuterium nuclei requires extreme temperature and
a. high pressure
b. radioactive fuel
c. cold water
dont understand this

The answer is A. high pressure. The fusion of two deuterium nuclei can only be done with high temperature and also highpressure to prevent electrostatic repulsion of the proton. The successful combination of the deuterium then creates helium as it all combines.
    Source: Objective Pre-Engineering Physics, Objective Questions with a Glossary of Knowledge wrote by Shobhana Sharma/ Google books

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