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1cse-2026-subject-07-002
CSE 2026Paper II10 Marks

Binding energy and rest mass energy of a two-nucleon bound state are denoted by B and Mc^2, respectively, where c is the speed of light. Calculate the minimum energy of a photon required to dissociate this bound state in terms of B and Mc^2.

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2cse-2026-subject-07-001
CSE 2026Paper II10 Marks

Are the nucleons inside the nucleus governed by the laws of quantum physics? Justify your answer.

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3cse-2026-subject-07-004
CSE 2026Paper II20 Marks

By considering the three-dimensional harmonic oscillator potential, explain the energy levels of nucleons inside the nucleus. Also, derive the zero-point energy of nucleons. Why did this assumption fail to explain the existence of nuclei with higher magic number?

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4cse-2026-subject-07-006
CSE 2026Paper II20 Marks

What is the criticality of a self-sustained nuclear reactor? Write the basic processes affecting the nuclear chain reactions of a finite-size nuclear reactor. Also, write the critical size of reactors of different shapes in terms of geometrical buckling constant.

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5cse-2026-subject-07-007
CSE 2026Paper II20 Marks

What do you understand by the \text{SU}(3) symmetry for the classification of baryons and mesons? Draw the octets for baryons and mesons along with their quarks and antiquarks.

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6cse-2026-subject-07-005
CSE 2026Paper II10 Marks

What do you understand by the packing fraction 'f' and the binding energy 'E_b' of a nucleus? Draw the graphs for packing fraction f versus mass number (A) and binding energy fraction f_b \left(= \dfrac{E_b}{A}\right) versus mass number (A). Further, explain how the graphs of the variation of f and f_b with A have complementary approaches.

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7cse-2026-subject-07-003
CSE 2026Paper II10 Marks

A nucleus of rest mass M is initially in an excited state whose energy is \Delta E above its ground state. The nucleus emits a \gamma-ray of energy h\nu and makes a transition to its ground state. Calculate the fractional change in energy for the nucleus.

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8ifos-2025-subject-07-005
IFOS 2025Paper II10 Marks

What do you understand by \text{SU}(3) symmetry for the quark model? On the basis of it, explain that the baryons can have +2 charge but mesons cannot have the same.

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9cse-2025-subject-07-004
CSE 2025Paper II15 Marks

What is the minimum energy required to break a {}_2^4\text{He} nucleus into free protons and neutrons? [ Given, m_{\text{H}} = 1\cdot 007825 \text{ amu}, m_n = 1\cdot 008665 \text{ amu}, m_e = 0\cdot 00055 \text{ amu} and m_{\text{He}} = 4\cdot 002603 \text{ amu} ]

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10ifos-2025-subject-07-002
IFOS 2025Paper II8 Marks
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11ifos-2025-subject-07-003
IFOS 2025Paper II20 Marks

By considering a suitable nuclear potential well for the deuteron ground state, show that it is a loosely bound nucleus.

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12cse-2025-subject-07-002
CSE 2025Paper II15 Marks

The total binding energies of {}_8^{15}\text{O}, {}_8^{16}\text{O} and {}_8^{17}\text{O} are 111\cdot 96 \text{ MeV}, 127\cdot 62 \text{ MeV} and 131\cdot 76 \text{ MeV} respectively. Determine the energy gap between 1p_{1/2} and 1d_{5/2} neutron shells for the nuclide whose mass number is close to 16.

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13ifos-2025-subject-07-004
IFOS 2025Paper II10 Marks
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14ifos-2025-subject-07-001
IFOS 2025Paper II8 Marks

Calculate the minimum energy (E_\gamma) required for a gamma ray photon to disintegrate a deuteron of mass M and binding energy B into a neutron and a proton. (Assume B \ll Mc^2)

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15cse-2025-subject-07-001
CSE 2025Paper II10 Marks

\rho^0 and \text{K}^0 mesons both decay mostly to \pi^+ and \pi^-. Why the mean lifetime of \rho^0 is 10^{-23} \text{ s}, whereas that of \text{K}^0 is 0\cdot 89 \times 10^{-10} \text{ s}?

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16cse-2025-subject-07-003
CSE 2025Paper II15 Marks

(i) \pi^- \rightarrow \mu^- + \bar{\nu}_\tau (ii) n \rightarrow p^+ + e^- + \bar{\nu}_e Explain the various leptonic family members. What is leptonic number conservation? Based on this conservation law, tell whether the following reactions are possible or not : (i) \pi^- \rightarrow \mu^- + \bar{\nu}_\tau (ii) n \rightarrow p^+ + e^- + \bar{\nu}_e

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17cse-2025-subject-07-006
CSE 2025Paper II10+10=20 Marks

State the basic assumption of single-particle shell model. How do the centrifugal and spin-orbit terms remove the degeneracy of three-dimensional spherical harmonic oscillator?

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18cse-2025-subject-07-005
CSE 2025Paper II15 Marks

Consider a uranium nucleus ({}_{92}\text{U}^{236}) breaking up spontaneously into two equal parts. Estimate the reduction of electrostatic energy of the nucleus considering uniform charge distribution. [ Assume that nuclear radius is 1\cdot 2 \times 10^{-13} A^{1/3} \text{ cm} ]

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19ifos-2024-subject-07-008
IFOS 2024Paper II15 Marks

What were the difficulties faced by the initial theory of \beta-decay? How did Pauli eliminate the difficulties? What were the expected properties of the new particle proposed by Pauli?

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20cse-2024-subject-07-001
CSE 2024Paper II10 Marks

For the ground state of deuteron, prove that the radius of nucleon is of the order of \sim 2\cdot 15 \times 10^{-13}\text{ cm}.

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