Nuclei

Assuming the experimental mass of 612C as 12 u, the mass defect of 612C 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).

1. 127.5
2. 89.03
3. 272.0
4. 92.0

Two nuclei of mass number 3 combine with another nucleus of mass number 4 to yield a nucleus of mass number 10. If the binding energy per nucleon for the mass numbers 3, 4 and 10 are 5.6 MeV, 7.4 MeV and 6.1 MeV, respectively, then in the process, Mc2= MeV.

1. 6.9
2. 7.9
3. 2.2
4. 4.3

The binding energy per nucleon of 20983Bi is MeV. [Take m( 20983Bi) = 208.980388 u, mp = 1.007825 u, mn = 1.008665 u, 1 u = 931 MeV/c2]

1. 7.48
2. 7.84
3. 8.79
4. 6.94

The binding energies for the following nuclear reactions are expressed in MeV. 2He3 + 0n1 2He4 + 20 MeV 2He4 + 0n1 2He5 - 0.9 MeV If X3, X4, X5 denote the stability of 2He3, 2He4 and 2He5, respectively, then the correct order is :

1. X4 > X5 > X3
2. X4 < X5 < X3
3. X4 > X5 < X3
4. X4 = X5 = X3

The minimum frequency of photon required to break a particle of mass 15.348 amu into 4 particles is kHz. [mass of He nucleus = 4.002 amu, 1 amu = 1.66 10-27 kg, h = 6.6 10-34 J s and c = 3 108 m/s]

1. 14.94 1020
2. 9 1019
3. 9 1020
4. 14.94 1019

Energy released when two deuterons (1H2 ) fuse to form a helium nucleus (2He4 ) is : (Given : Binding energy per nucleon of 1H2 = 1.1 MeV and binding energy per nucleon of 2He4 = 7.0 MeV)

1. 26.8 MeV
2. 8.1 MeV
3. 23.6 MeV
4. 5.9 MeV