Assertion and Reason for Nuclei Mass and Neutrons – Rankers Physics

Nucleus: Practice Problem & Solution

Assertion (A): A nuclei has mass more than the sum of the masses of the individual nucleons in them. Reason (R): In nuclei, number of neutrons is less than the number of electrons.  
(1) Both (A) & (R) are true and the (R) is the correct explanation of the (A)
(2) Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(3) (A) is true but (R) is false
(4) 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 false because of mass defect; the nucleus mass is less than the sum of constituent nucleons. Reason (R) is false as neutrons are in the nucleus and electrons orbit outside. Thus, both (A) and (R) are false.

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