Nucleus: Practice Problem & Solution

Short Solution (Best for NEET):

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

The effective Rydberg constant for an atom depends on the reduced mass \( \mu = \frac{m_e M}{m_e + M} \), where \( M \) is the nuclear mass (related to mass number). So, (A) is true. The reduced mass clearly depends on the nuclear mass. So (R) is true. (R) correctly explains (A).