Question

A carbon-12 atom has a mass defect of 0.09564 amu.

Which setup is used to calculate nuclear binding energy?

0.09564 amu x (1.6606 x 10–27 kg)/amu x (3.0 x 108)2

0.09564 amu x 1 amu/(1.6606 x 10–27 kg) x (3.0 x 108)2

0.09564 amu x (3.0 x 108)2

0.09564 amu x (1.6606 x 10–27 kg)/amu x (3.0 x 108)

Answer 1

Answer: the first setup.

Reason: convert the mass defect from amu to kg, then use E = mc^2:
0.09564 amu × (1.6606×10^−27 kg/amu) × (3.0×10^8 m/s)^2.

This gives E ≈ 1.43×10^−11 J ≈ 89 MeV.