Atoms & Nuclei

JEE Main level, single correct, medium

170 of 239

Question 170 of 239

The ratio of the density of oxygen nucleus (O816)\left(O816\right) and helium nucleus (He24)\left(He24\right) is

Show answer and solution

Answer: (C) 1:11:1

The radius of a nucleus, RR is related to its atomic number AA as:
R=R0A13R={R}_{0}{A}^{\dfrac{1}{3}}
where R0{R}_{0} is the nuclear radius of hydrogen.
Thus, the density of a nucleus is given by:
d=μA43π(R0A13)3=3μ4πR03=Constantd=\dfrac{\mu A}{\dfrac{4}{3}\pi {\left({R}_{0}{A}^{\dfrac{1}{3}}\right)}^{3}}=\dfrac{3\mu }{4\pi {R}_{0}^{3}}=\text{Constant}
(Here, μ\mu is atomic mass unit)
Hence, the ratio of nuclear density of oxygen to helium nucleus is 1:11:1

JEE Main question paper PDF

Open a shift to read the full paper on this page, or download it.

JEE Main 2025 Apr 2 Shift 1 question paper

Open Download PDF

Opening paper…

Explain it as a whiteboard videoStep-by-step, in Hinglish or English. Your first video needs no login.Solved it on paper but got it wrong?Upload a photo of your working. Mistake Doctor marks the exact line that broke.
See it move: Atoms: Rutherford, Bohr and X-rays simulationDrag the sliders and watch the numbers in this question change.Revise Modern Physics firstFormula sheet, solved examples and the traps students fall into.

More Physics practice

JEE Main Physics practice question on Atoms & Nuclei (Nuclear structure), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.