Which of the following pairs of nuclei are isobars of the element?

${ }_1^3 \mathrm{H}$ and ${ }_2^3 \mathrm{He}$

${ }_{80}^{198} \mathrm{Hg}$ and ${ }_{79}^{197} \mathrm{Au}$

${ }_1^2 \mathrm{H}$ and ${ }_1^3 \mathrm{H}$

${ }_{92}^{236} \mathrm{U}$ and ${ }_{92}^{238} \mathrm{U}$

The energy E and momentum p of a moving body of mass m are related by some equation. Given that c represents the speed of light, identify the correct equation

$\mathrm{E}^2=\mathrm{p}^2 \mathrm{c}^2+\mathrm{m}^2 \mathrm{c}^4$

$\mathrm{E}^2=\mathrm{pc}^2+\mathrm{m}^2 \mathrm{c}^4$

$\mathrm{E}^2=\mathrm{pc}^2+\mathrm{m}^2 \mathrm{c}^2$

$\mathrm{E}^2=\mathrm{p}^2 \mathrm{c}^2+\mathrm{m}^2 \mathrm{c}^2$

Given below are two statements : Statement (I) : The dimensions of Planck's constant and angular momentum are same. Statement (II) : In Bohr's model electron revolves around the nucleus only in those orbits for which angular momentum is integral multiple of Planck's constant. In the light of the above statements, choose the most appropriate answer from the options given below :

Statement I is correct but Statement II is incorrect

Both Statement I and Statement II are correct

Both Statement I and Statement II are incorrect

Statement I is incorrect but Statement II is correct

Atoms And Nuclei — JEE Main Previous Year Questions

185 solved PYQs · 2016–2026 · Physics

Solved PYQs: 185
Years covered: 2016–2026
Avg / year: ~17
Subject: Physics

How many JEE Main questions come from Atoms And Nuclei?

Atoms And Nuclei has contributed 185 questions to Joint Entrance Examination (Main) papers between 2016 and 2026 — an average of about 17 questions a year. That count is measured from EByAi’s bank of 55,289 JEE Main questions, not estimated from a syllabus. Every one of the 185 questions carries a written, step-by-step solution, and each is tagged to Atoms And Nuclei within Physics, so you can drill this chapter across every year at once instead of hunting through paper PDFs. Practising a chapter’s full PYQ history is the fastest way to learn the patterns examiners reuse.

Sample Atoms And Nuclei questions from real JEE Main papers

These are 5 real questions from the bank — exactly as asked, with the answer one tap away. All 185 Atoms And Nuclei questions (with full written solutions) are available in practice.

Question 1 · JEE Main 2026
Which of the following pairs of nuclei are isobars of the element?
1. (A) $_{1}^{3} H and_{2}^{3} He$
2. (B) $_{80}^{198} Hg and_{79}^{197} Au$
3. (C) $_{1}^{2} H and_{1}^{3} H$
4. (D) $_{92}^{236} U and_{92}^{238} U$
Show answerAnswer
$Answer: (A)_{1}^{3} H and_{2}^{3} He$
Question 2 · JEE Main 2025
For a nucleus of mass number A and radius R, the mass density of nucleus can be represented as
1. (A) $A^{\frac{2}{3}}$
2. (B) $Independent of A$
3. (C) $A^{3}$
4. (D) $A^{\frac{1}{3}}$
Show answerAnswer
$Answer: (B) Independent of A$
Question 3 · JEE Main 2025
The frequency of revolution of the electron in Bohr's orbit varies with n , the principal quantum number as:
1. (A) $\frac{1}{n ^{4}}$
2. (B) $\frac{1}{n ^{2}}$
3. (C) $\frac{1}{n ^{3}}$
4. (D) $\frac{1}{n}$
Show answerAnswer
$Answer: (C) \frac{1}{n ^{3}}$
Question 4 · JEE Main 2025
The energy E and momentum p of a moving body of mass m are related by some equation. Given that c represents the speed of light, identify the correct equation
1. (A) $E^{2} = pc^{2} + m^{2} c^{4}$
2. (B) $E^{2} = pc^{2} + m^{2} c^{2}$
3. (C) $E^{2} = p^{2} c^{2} + m^{2} c^{4}$
4. (D) $E^{2} = p^{2} c^{2} + m^{2} c^{2}$
Show answerAnswer
$Answer: (C) E^{2} = p^{2} c^{2} + m^{2} c^{4}$
Question 5 · JEE Main 2025
Given below are two statements : Statement (I) : The dimensions of Planck's constant and angular momentum are same. Statement (II) : In Bohr's model electron revolves around the nucleus only in those orbits for which angular momentum is integral multiple of Planck's constant. In the light of the above statements, choose the most appropriate answer from the options given below :
1. (A) $Both Statement I and Statement II are correct$
2. (B) $Statement I is correct but Statement II is incorrect$
3. (C) $Both Statement I and Statement II are incorrect$
4. (D) $Statement I is incorrect but Statement II is correct$
Show answerAnswer
$Answer: (B) Statement I is correct but Statement II is incorrect$

Atoms And Nuclei questions by year

Year	Questions	Share of chapter questions
2026	24
2025	20
2024	40
2023	29
2022	19
2021	17
2020	12
2019	12
2018	6
2017	5
2016	1

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FAQs

How many JEE Main questions have been asked from Atoms And Nuclei?

EByAi's bank holds 185 real JEE Main questions from Atoms And Nuclei, asked between 2016 and 2026 — about 17 per year on average. Every count is measured from actual papers, not estimated.

Is Atoms And Nuclei important for JEE Main?

185 questions over 11 papers make Atoms And Nuclei a moderate-weightage chapter in JEE Main Physics. The year-wise table above shows exactly how often it appears.

Can I solve Atoms And Nuclei PYQs online for free?

Yes. EByAi lets you solve JEE Main past-year questions in the browser with written solutions — free daily practice, no card needed.

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