NEETPhysicsNuclear Physics
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The rest mass of a stable nucleus is always less than the sum of the rest masses of its constituent protons and neutrons. Reason (R): According to Einstein's mass-energy equivalence, the 'missing' mass is converted into binding energy that is released when the nucleus is broken apart into its const
Options
- ABoth Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
- BBoth Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
- CAssertion (A) is true but Reason (R) is false.
- DAssertion (A) is false but Reason (R) is true.
Correct answer
C. Assertion (A) is true but Reason (R) is false.
Step-by-step solution
Assertion (A) is true: The mass of a stable nucleus is always less than the sum of the masses of its constituent nucleons. This difference is known as the mass defect. Reason (R) is false: When a nucleus is formed from its constituent nucleons, energy is released. Conversely, to break a stable nucleus apart into its constituent free nucleons, energy equal to the binding energy must be supplied to the nucleus, not released. Therefore, Assertion (A) is true but Reason (R) is false. Answer: Assertion (A) is true but R