JEE Main 2026 · 5 Apr · Shift 2 · Physics Q44

PhysicsSingle correct+4 / -1Question 44 of 75

Assuming the experimental mass of $^{12}_{\ 6}\mathrm C$ as 12 u, the mass defect of $^{12}_{\ 6}\mathrm C$ atom is ________ MeV/c².

(Mass of proton = 1.00727 u, mass of neutron = 1.00866 u, 1 u = 931.5 MeV/c² and c is the speed of the light in vacuum).

127.5

89.03

272.0

92.0

Answer and worked solution

Official answer: B

Mass defect (using the given proton and neutron masses):
$6(1.00727)+6(1.00866)-12=0.09558\text{ u}.$

In MeV. $0.09558\times931.5\approx89.03$ MeV/c².

(B)

Topics:Mass defect and binding energy

JEE Main 2026 · 5 Apr · Shift 2, Physics question 44