Question
Physics Question on Nuclei
Find the energy equivalent of one atomic mass unit in joules and in MeV.
A
1.66×10−10J,93.15MeV.
B
2.5×10−10J,931.5MeV.
C
1.5×10−10J,931.5MeV.
D
3×10−10J,9.315MeV.
Answer
1.5×10−10J,931.5MeV.
Explanation
Solution
Here, m=1u=1.6605×10−27kg
According to Einstein's mass-energy equivalence relation
E=mc2
=(1.6605×10−27kg)(2.9979×108ms−1)2
=1.4924×10−10J=1.5×10−10J
E=1.602×10−191.4924×10−10eV
=0.9315×109eV=931.5×106eV=931.5MeV