ρ= VM=34πR3mn×A=34πAR03mn×A
So ρ is almost is constant
$\begin{aligned}
& \mathrm{R}=\mathrm{R}_0 \mathrm{A}^{1 / 3} \
& \mathrm{R} \propto \mathrm{A}^{1 / 3}
\end{aligned}$
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The density of the copper (…
JEE Main 2025 — Physics Modern Physics
2025mcqeasy
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : The density of the copper (2964Cu) nucleus is greater than that of the carbon (612C) nucleus.
Reason (R): The nucleus of mass number A has a radius proportional to A1/3.
In the light of the above statements, choose the most appropriate answer from the options given below :
Official previous-year question
Held on 7 Apr 2025 · Verified 6 Jul 2026.
Options
- A
(A) is correct but (R) is not correct
- B
(A) is not correct but (R) is correct
- C
Both (A) and (R) are correct and (R) is the correct explanation of (A)
- D
Both (A) and (R) are correct but (R) is not the correct explanation of (A)
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