Mass Defect & Binding Energy MCQs
Mass Defect & Binding Energy MCQs
Class: CBSE Class 12 | Subject: Physics
Section 8: Atoms and Nuclei
Topic: Mass Defect & Binding Energy
Based on CBSE Board Examination Pattern
Section 8: Atoms and Nuclei
Topic: Mass Defect & Binding Energy
Based on CBSE Board Examination Pattern
Instructions: These Multiple Choice Questions (MCQs) are designed strictly as per the NCERT syllabus, making them ideal for CBSE Class 12 Board Examination preparation.
1. Mass defect of a nucleus is defined as:
Answer: B
Mass defect is the difference between the sum of masses of individual nucleons and the actual mass of the nucleus. This missing mass converts into binding energy.
Mass defect is the difference between the sum of masses of individual nucleons and the actual mass of the nucleus. This missing mass converts into binding energy.
2. Binding energy of a nucleus arises due to:
Answer: B
Binding energy is due to strong nuclear force that holds nucleons together against electrostatic repulsion.
Binding energy is due to strong nuclear force that holds nucleons together against electrostatic repulsion.
3. Binding energy is related to mass defect by:
Answer: B
Einstein’s mass–energy relation shows that small mass converts into large nuclear binding energy.
Einstein’s mass–energy relation shows that small mass converts into large nuclear binding energy.
4. Unit of binding energy commonly used in nuclear physics:
Answer: C
Binding energy is very large at nuclear scale, hence expressed in MeV.
Binding energy is very large at nuclear scale, hence expressed in MeV.
5. Higher binding energy per nucleon implies:
Answer: B
Greater binding energy per nucleon means nucleons are more tightly bound → nucleus is more stable.
Greater binding energy per nucleon means nucleons are more tightly bound → nucleus is more stable.
6. Binding energy per nucleon is maximum for:
Answer: C
Iron‑56 lies at peak of binding energy curve → most stable.
Iron‑56 lies at peak of binding energy curve → most stable.
7. Mass defect is measured in:
Answer: D
It is a mass quantity measured in kg or atomic mass unit.
It is a mass quantity measured in kg or atomic mass unit.
8. 1 amu energy equivalent ≈
Answer: A
1 amu = 931 MeV energy equivalent.
1 amu = 931 MeV energy equivalent.
9. Cause of mass defect:
Answer: B
Energy released during nucleus formation reduces mass.
Energy released during nucleus formation reduces mass.
10. Binding energy curve explains:
Answer: D
Curve predicts fusion (light nuclei) & fission (heavy nuclei).
Curve predicts fusion (light nuclei) & fission (heavy nuclei).
11. If binding energy increases, mass defect:
Answer: B
Greater converted mass → higher binding energy.
Greater converted mass → higher binding energy.
12. Nuclear stability depends on:
Answer: D
All factors influence nuclear stability.
All factors influence nuclear stability.
13. Energy to break nucleus completely:
Answer: B
Binding energy equals energy required to separate nucleons.
Binding energy equals energy required to separate nucleons.
14. Light nuclei release energy by:
Answer: B
Fusion increases binding energy per nucleon.
Fusion increases binding energy per nucleon.
15. Heavy nuclei release energy by:
Answer: B
Fission products have higher binding energy.
Fission products have higher binding energy.
16. Binding energy per nucleon unit:
Answer: B
It is energy per nucleon → MeV/nucleon.
It is energy per nucleon → MeV/nucleon.
17. Most stable nuclei lie near mass number:
Answer: B
Iron region (~56) shows maximum stability.
Iron region (~56) shows maximum stability.
18. Nuclear force is:
Answer: B
Acts only over nuclear dimensions (~fm).
Acts only over nuclear dimensions (~fm).
19. Binding energy curve peak indicates:
Answer: B
Peak corresponds to most stable nuclei.
Peak corresponds to most stable nuclei.
20. Mass defect converted energy appears as:
Answer: D
Nuclear energy distributes in multiple forms.
Nuclear energy distributes in multiple forms.