College Physics 10th Edition by Raymond Serway,Chris Vuille

Exercise 39

A reaction that has been considered as a source of energy is the absorption of a proton by a boron-11 nucleus to produce three alpha particles:
This reaction is an attractive possibility because boron is easily obtained from Earth's crust. A disadvantage is that the protons and boron nuclei must have large kinetic energies for the reaction to take place. This requirement contrasts to the initiation of uranium fission by slow neutrons. (a) How much energy is released in each reaction (b) Why must the reactant particles have high kinetic energies