विकिरण तथा द्रव्य की द्वैत प्रकृति — बार-बार पूछे जाने वाले प्रश्न
Last updated: 5 July 2026
Every RBSE Class 12 Physics board paper from 2013 to 2026 for Dual Nature of Radiation and Matter, sorted and tagged so you know exactly which Einstein's-photoelectric-equation, threshold-frequency and de-Broglie-wavelength questions to revise first.
Real previous-year questions with the exact RBSE board years they appeared in. 5 more high-yield questions — including stopping-potential numericals — are in the free PDF.
Derive Einstein's photoelectric equation. Explain the photoelectric effect with the help of this equation.
आइन्सटीन का प्रकाश-विद्युत समीकरण लिखकर, इससे प्रकाश-विद्युत प्रभाव से सम्बन्धित कोई दो प्रेक्षणों की व्याख्या कीजिए।
🔥 Most repeated · asked 2×Why can the photoelectric effect not be explained on the basis of the wave theory of light? Write any two reasons.
प्रकाश-विद्युत प्रभाव की व्याख्या प्रकाश के तरंग सिद्धान्त के आधार पर क्यों नहीं की जा सकती है? कोई दो कारण लिखिए।
🔁 Repeated · asked 2×Write the definition of threshold frequency of a substance.
किसी पदार्थ की 'देहली आवृत्ति' की परिभाषा लिखिए।
🔁 Repeated · asked 2×Write Einstein's photoelectric equation. Derive a relation between stopping potential V₀ and frequency ν of incident light. Draw a graph between stopping potential and frequency for two different metals.
आइंस्टाइन का प्रकाश विद्युत समीकरण लिखिए। आपतित प्रकाश की आवृत्ति ν तथा निरोधी विभव V₀ के मध्य सम्बन्ध स्थापित कीजिए। दो भिन्न धातुओं के लिए निरोधी विभव तथा आपतित प्रकाश की आवृत्ति के मध्य ग्राफ खींचिए।
⭐ High-weightage derivationWhat is the photoelectric effect? Draw a diagram of the experimental arrangement used to study it. Explain the effect of potential on photoelectric current when the intensity of incident light is constant.
प्रकाश विद्युत प्रभाव क्या है? इसके अध्ययन के लिए की गई प्रायोगिक व्यवस्था का चित्र बनाइये। प्रकाश विद्युत धारा पर आपतित प्रकाश की तीव्रता नियत रखते हुए विभव का क्या प्रभाव होता है? ग्राफ बनाइये।
⚙️ Core experimentThe other 5 are in the free PDF — and all 39 previous-year questions for this chapter are in the full book.
Get 10 hand-picked previous-year questions from Chapter 11. 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 11 (Dual Nature of Radiation and Matter) is tested every year without fail. It belongs to Unit VII — Dual Nature of Radiation and Matter and is drawn from a pool of 39 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 0.5 to 1-mark openers on stopping potential, work function or de Broglie wavelength calculations. The 1.5-mark questions lean on Einstein's photoelectric equation and the wave-theory limitations of the photoelectric effect. The heavy marks sit in the 3-mark long answers, which ask you to derive the stopping-potential–frequency relation or describe the photoelectric experimental setup.
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.
"Einstein's photoelectric equation wala proof do baar repeat ho chuka hai — sabse upar rakha gaya list mein."
"De Broglie wavelength ke numericals free sample mein the, calculation practice ho gayi."
"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 39 tagged previous-year questions for Dual Nature of Radiation and Matter — plus all 13 other chapters.
Every MCQ, VSA, SA and long-answer question for this chapter from RBSE papers 2013–2026 — 39 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 dual nature of radiation and matter formula — Einstein's photoelectric equation, stopping potential and de Broglie wavelength 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 →