Q. The binding energy per nucleon in deuterium and helium nuclei are 1.1 MeV and 7.0 MeV, respectively. When two deuterium nuclei fuse to form a helium nucleus the energy released in the fusion is
A) 23.6 MeV
B) 2.2 MeV
C) 28.0 MeV
D) 30.2 MeV
Explanation
[Solution from source] Binding energy of two deuterons = 2 × (2 × 1.1) = 4.4 MeV; of helium-4 = 4 × 7.0 = 28.0 MeV. Energy released = 28.0 − 4.4 = 23.6 MeV. 28.0 MeV is just the helium binding energy without subtracting that of the reactants. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.