PHYSICS
JAMB 2004 - Question 21
Physics 2004 JAMB Past Questions - Question 21: The binding energy of helium4 2He is (mass of proton =1.00783u)(mass of neutron=1.00867u)
Choose the correct answers from the options given.
(mass of proton =1.00783u)(mass of neutron=1.00867u)
A:
B:
C:
D:
Correct Answer
C
Explanation
The binding energy of a nucleus, is the work done or energy needed to separate completely the nucleons (protons and neutrons) apart. Again, experiment shows that the total mass of all individual nucleons is greater than that of the nucleus, in which they are together. This difference in the mass is the measure of the binding energy of the particular nucleus.
For helium4He,2
it has altogether 4 nucleons 2 protons and 2 neutrons
2:H = 2 x 1.00783 = 2.01566
2:n = 2 x 1.00867 = 2.01734
∴ 2:H + 2:n = 4.03300u
But the helium nucleus has a mass of 4.00260u
∴ Binding energy = difference of nucleons and nucleus
= 4.03300U - 4.00260U = 0.03040U

