किरण प्रकाशिकी एवं प्रकाशिक यंत्र — बार-बार पूछे जाने वाले प्रश्न
Last updated: 5 July 2026
Every RBSE Class 12 Physics board paper from 2013 to 2026 for Ray Optics and Optical Instruments, sorted and tagged so you know exactly which mirror-formula, lens-maker's-formula and telescope/microscope questions to revise first.
Real previous-year questions with the exact RBSE board years they appeared in. 5 more high-yield questions — including prism-angle and telescope derivations — are in the free PDF.
Write the relation between object distance (u), image distance (v) and focal length (f) for a concave mirror.
अवतल दर्पण द्वारा प्रतिबिम्ब रचना का किरण चित्र बनाकर बिम्ब की दूरी (u), प्रतिबिम्ब दूरी (v) तथा फोकस दूरी (f) में संबंध स्थापित कीजिए।
🔥 Most repeated · asked 4×Define total internal reflection.
पूर्ण आन्तरिक परावर्तन की परिभाषा लिखिए।
🔁 Repeated · asked 2×If the focal length of a concave mirror is f and the radius of curvature is R, prove that the radius of curvature is twice the focal length.
यदि एक अवतल दर्पण की फोकस दूरी f एवं वक्रता त्रिज्या R है, तो सिद्ध कीजिए कि वक्रता त्रिज्या फोकस दूरी की दुगुनी होती है।
🔁 Repeated · asked 2×Derive the lens maker's formula 1/f = (n−1)(1/R₁ − 1/R₂). Also explain the effect on the image when the lower half of a concave mirror's reflecting surface is covered with an opaque material.
लेंस मेकर सूत्र 1/f = (n-1)(1/R₁ - 1/R₂) व्युत्पन्न कीजिए। किसी अवतल दर्पण का निचला आधा परावर्तक तल किसी अपारदर्शी पदार्थ से ढक दें तो दर्पण द्वारा बने प्रतिबिम्ब पर क्या प्रभाव पड़ेगा?
⭐ High-weightage derivationDescribe the construction of a compound microscope. Derive an expression for its total magnification. Draw a ray diagram for the formation of an image by a compound microscope.
संयुक्त सूक्ष्मदर्शी से क्या तात्पर्य है? संयुक्त सूक्ष्मदर्शी द्वारा प्रतिबिम्ब बनने का किरण आरेख बनाइए। इसकी कार्यप्रणाली का संक्षिप्त वर्णन कर इसके कुल आवर्धन का सूत्र व्युत्पन्न कीजिए।
⚙️ Core derivationThe other 5 are in the free PDF — and all 45 previous-year questions for this chapter are in the full book.
Get 10 hand-picked previous-year questions from Chapter 9. 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 9 (Ray Optics and Optical Instruments) is tested every year without fail. It belongs to Unit VI — Optics and is drawn from a pool of 45 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 1-mark openers on radius of curvature, total internal reflection or power of a lens. The 1.5 to 2-mark questions lean on mirror and lens numericals. The heavy marks sit in the 3 to 4-mark long answers, which rotate between the u-v-f relation for a concave mirror (RBSE's single most-repeated question in this chapter), the lens maker's formula, and the compound microscope or telescope derivation — with 45 questions in the full pool, this is the largest chapter in the book, so the free sample focuses only on its highest-yield picks.
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.
"Concave mirror ka u-v-f wala question har saal ghoom fir ke aata hai — sabse pehle isi list mein dekha."
"45 questions ka sabse bada chapter hai, free sample mein top wale mil gaye, revision plan ban gaya."
"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 45 tagged previous-year questions for Ray Optics and Optical Instruments — plus all 13 other chapters.
Every MCQ, VSA, SA and long-answer question for this chapter from RBSE papers 2013–2026 — 45 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 ray optics and optical instruments formula — mirror formula, lens maker's formula, prism-angle and magnifying-power 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 →