परमाणु — बार-बार पूछे जाने वाले प्रश्न
Last updated: 5 July 2026
Every RBSE Class 12 Physics board paper from 2013 to 2026 for Atoms, sorted and tagged so you know exactly which Bohr's-postulates, Rutherford-model-drawbacks and hydrogen-spectrum questions to revise first.
Real previous-year questions with the exact RBSE board years they appeared in. 5 more high-yield questions — including orbital-velocity and energy-level numericals — are in the free PDF.
Explain Bohr's second postulate of quantisation using the de Broglie hypothesis.
डी ब्रोग्ली परिकल्पना से बोर के क्वांटमीकरण के द्वितीय अभिग्रहीत की व्याख्या कीजिए।
🔥 Most repeated · asked 3×Write two drawbacks of Rutherford's atomic model.
परमाणु के रदरफोर्ड मॉडल की दो कमियाँ लिखिए।
🔁 Repeated · asked 2×Write two limitations of Bohr's model.
बोर मॉडल की दो सीमाऐं लिखिए।
🔁 Repeated · asked 2×The total energy of the electron in the ground state of a hydrogen atom is −13.6 eV. Find the kinetic energy and the potential energy of the electron in this state.
हाइड्रोजन परमाणु की निम्नतम अवस्था में कुल ऊर्जा -13.6 eV है। इस दशा में इलेक्ट्रॉन की गतिज ऊर्जा तथा स्थितिज ऊर्जा ज्ञात करे।
⚙️ Core numericalOn the basis of Bohr's postulates, derive an expression for the orbital velocity of an electron in the nth stationary orbit of a hydrogen atom.
बोर के अभिगृहीतों के आधार पर हाइड्रोजन परमाणु की n वीं स्थाई कक्षा में इलेक्ट्रॉन के कक्षीय वेग के व्यंजक की व्युत्पत्ति कीजिए।
⭐ High-weightage derivationThe other 5 are in the free PDF — and all 21 previous-year questions for this chapter are in the full book.
Get 10 hand-picked previous-year questions from Chapter 12. Every question includes the exam year, marks, and repeat count. Instant download—no signup required.
A quick map of the chapter before you download — so you know what the questions are testing.
If you have gone through the last decade of RBSE Class 12 Physics papers, you will notice Chapter 12 (Atoms) is tested every year without fail. It belongs to Unit VIII — Atoms and Nuclei and is drawn from a pool of 21 previous-year questions spanning 2013–2026, spread across MCQs, very short, short and long-answer sections. The topics rotate, but the question patterns stay remarkably steady.
Expect a quick 0.5 to 1-mark opener on scattering angle, excitation energy or hydrogen spectral series. The 1.5 to 2-mark questions lean on the drawbacks of Rutherford's model, the limitations of Bohr's model, and ground-state kinetic/potential energy numericals. The most repeated question asks you to explain Bohr's second postulate of quantisation using the de Broglie hypothesis.
So the smart way to revise this chapter is not to read it end to end, but to practise the questions RBSE actually repeats. The five questions above — and the ten in the free sample PDF — are taken straight from real board papers and tagged with the exact years they appeared, so you can see for yourself what the full RBSE Physics chapterwise PYQ book offers before you decide to buy it.
The RBSE syllabus sub-topics this chapter's PYQs are drawn from — useful for scoping your revision even if you're not buying the full book.
"Bohr's second postulate wala question teen baar repeat ho chuka hai, is baar bhi expect kar raha hoon."
"Rutherford model ki drawbacks aur Bohr's limitations wale questions free PDF mein clearly tagged the."
"Year-wise tags dekh kar revision plan banana easy ho gaya. Poora 14-chapter book bhi le liya sirf ₹59 mein, paisa vasool."
The ₹59 full book unlocks all 21 tagged previous-year questions for Atoms — plus all 13 other chapters.
Every MCQ, VSA, SA and long-answer question for this chapter from RBSE papers 2013–2026 — 21 in total.
Each question labelled with year, marks and question type.
Highest-repeated questions listed first so revision time is spent well.
Full bilingual coverage — study in whichever medium you write your exam.
Quick-reference sheet of every atoms formula — Bohr radius, orbital velocity, energy-level and Rydberg formulas.
Updated to the latest RBSE board pattern, with access valid for the current 2026–27 exam session.
One booklet, every chapter, tagged and sorted by repeat priority — in English and Hindi.
See full book — ₹59 →