Nucleus Stability and Proton-Neutron Ratio – Rankers Physics

Nucleus: Practice Problem & Solution

Assertion (A): If number of protons in a nucleus is more than number of neutrons present, the nucleus is unstable. Reason (R): Electrostatic force between two protons in a nucleus dominates over the nuclear force between them.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Nucleus. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is true. Nuclei with a significant excess of protons over neutrons ((Z > N)) are generally unstable due to increased electrostatic repulsion. Reason (R) is false.

The strong nuclear force is much stronger than the electrostatic force between two protons at nuclear distances. Nuclear instability arises from the cumulative effect of long-range electrostatic repulsion overcoming the short-range strong nuclear attraction for a large number of protons.

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