Nuclei

Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the correct answer from the options given below :

1. (A) is true but (R) is false
2. Both (A) and (R) are true and (R) is the correct explanation of (A)
3. (A) is false but (R) is true
4. Both (A) and (R) are true but (R) is NOT the correct explanation of (A)

The energy equivalent of 1 g of substance is :

1. 5.6 1026 MeV
2. 5.6 1012 MeV
3. 5.6 eV
4. 11.2 1024 MeV

A star has 100\% helium composition. It starts to convert three 4He into one 12C via triple alpha process as 4He + 4He + 4He 12C + Q. The mass of the star is 2.0 1032 kg and it generates energy at the rate of 5.808 1030 W. The rate of converting these 4He to 12C is n 1042 s-1, where n is . [Take, mass of 4He = 4.0026 u, mass of 12C = 12 u]

The energy released in the fusion of 2 kg of hydrogen deep in the sun is EH and the energy released in the fission of 2 kg of 235U is EU. The ratio EHEU is approximately: (Consider the fusion reaction as 4 11H + 2e- 24He + 2 + 6 + 26.7 MeV, energy released in the fission reaction of 235U is 200 MeV per fission nucleus and NA = 6.023 1023)

1. 7.62
2. 25.6
3. 9.13
4. 15.04

Binding energy of a certain nucleus is 18 108 J. How much is the difference between total mass of all the nucleons and nuclear mass of the given nucleus:

1. 20 g
2. 2 g
3. 10 g
4. 0.2 g

If M0 is the mass of isotope 125B, Mp and Mn are the masses of proton and neutron, then nuclear binding energy of isotope is:

1. (5Mp + 7Mn - M0)C2
2. (M0 - 5Mp - 7Mn)C2
3. (M0 - 5Mp)C2
4. (M0 - 12Mn)C2

In a hypothetical fission reaction 92X236 56Y141 + 36Z92 + 3R The identity of emitted particles (R) is :

1. Proton
2. Neutron
3. Electron
4. -radiations

If three helium nuclei combine to form a carbon nucleus then the energy released in this reaction is 10-2 MeV. (Given 1 u = 931 MeV/c2, atomic mass of helium = 4.002603 u)

Which of the following nuclear fragments corresponding to nuclear fission between neutron (01n ) and uranium isotope (92235U ) is correct :

1. 56140Xe+3894Sr+301n
2. 51153Sb+4199Nb+301n
3. 56144Ba+3689Kr+401n
4. 56144Ba+3689Kr+301n

The disintegration energy Q for the nuclear fission of 235U 140Ce + 94Zr + n is MeV. Given atomic masses of 235U : 235.0439 u; 140Ce : 139.9054 u, 94Zr : 93.9063 u; n : 1.0086 u, Value of c2 = 931 MeV/u.