Optics — Class 11 MCQs with Answers
Class 11 CBSE Physics · Chapter 303
40 practice questions · 20 Easy · 20 Medium · Updated
Practise the most important Class 11 CBSE Physics questions from Chapter 303, "Optics". You get 4 timed quizzes made from 40 NCERT-based MCQs, with answers and explanations. The questions are split into 20 Easy and 20 Medium. Warm up on the basics, then move on to the exam-level questions that set top scorers in CBSE & Maharashtra HSC Board exams, JEE Main, MHT-CET, JEE Advanced and NEET UG apart.
To score well in "Optics", focus on numericals, derivations and applying concepts. Each MCQ here is timed and uses exam-style marking (+4 correct, −1 wrong, 0 skipped). This trains you to stay accurate under time pressure, as real papers need. Every question has a short explanation, so a wrong answer becomes a quick lesson. It is the fastest way to fix gaps before a test.
Use this chapter for focused revision. Start with the Easy set to check your basics on Optics, then move to Medium to practise applying them. Your accuracy, streaks and XP save automatically. This chapter also adds to your overall Class 11 Physics mastery score. 6 sample questions are solved in full below, with the answer and a worked explanation. Sign in free to start practising.
Key concepts: Optics (Class 11 Physics)
Light treated as rays: reflection at spherical mirrors with the mirror formula and sign convention, refraction and Snell's law, total internal reflection with its applications, refraction at a spherical surface leading to the lens maker's formula, lens power and combinations, the prism, and the microscope and telescope. Light treated as a wave: Huygens' principle and wavefronts, coherence and interference in Young's double-slit experiment with its fringe width, diffraction at a single slit and the width of the central maximum, how interference differs from diffraction, and polarisation with Malus's and Brewster's laws.
- Laws of reflection
- The angle of incidence equals the angle of reflection, and the incident ray, reflected ray and normal all lie in one plane.
- Spherical mirrors
- A concave mirror converges light and can form real or virtual images; a convex mirror always diverges and forms only virtual, diminished images.
- Sign convention
- Distances are measured from the pole, positive along the incident light and negative against it. Nearly every optics error traces back to a sign here.
- Mirror formula and magnification
- One relation links object distance, image distance and focal length, with magnification −v/u telling you the size and orientation of the image.
Optics — important questions & MCQs with answers (Class 11 Physics)
6 solved questions from this chapter's difficulty levels, each with its answer and explanation. The other 34 are timed and scored when you sign in.
- Q1Easy
Snell's law:
A.NoneB.n₁ + n₂ = θC.n = c/v onlyD.n₁ sinθ₁ = n₂ sinθ₂✓ CorrectAnswer: D. n₁ sinθ₁ = n₂ sinθ₂
Explanation: Refraction at interface.
- Q2Easy
Young's experiment demonstrates:
A.Interference of light✓ CorrectB.Reflection onlyC.Refraction onlyD.Photoelectric effectAnswer: A. Interference of light
Explanation: Two-slit interference pattern.
- Q3Easy
Light is polarised because it is:
A.SoundB.LongitudinalC.MechanicalD.A transverse wave✓ CorrectAnswer: D. A transverse wave
Explanation: Only transverse waves can be polarised.
- Q4Medium
Total internal reflection occurs when:
A.Light passes from denser to rarer beyond critical angle✓ CorrectB.At normal incidenceC.AlwaysD.In vacuumAnswer: A. Light passes from denser to rarer beyond critical angle
Explanation: Used in optical fibres.
- Q5Medium
Fringe width β =
A.λ/dB.d/λDC.λD/d✓ CorrectD.λDAnswer: C. λD/d
Explanation: D = screen distance, d = slit sep.
- Q6Medium
Width of central maximum in single-slit diffraction (screen at D, slit a):
A.λ/aB.λD/aC.2λD/a✓ CorrectD.a/DAnswer: C. 2λD/a
Explanation: From first minima on either side.
Start this chapter free
You have 6 solved above. Sign in with Google (no card needed). You get 1 Easy + 1 Medium quiz on every chapter during your 30-day trial. After that, you keep 1 Easy quiz on every chapter, free for good, plus the full key-concept notes, formulas & exam tips.
This chapter has 40 questions (20 Easy · 20 Medium), with timed scoring and instant feedback. The rest unlock with the ₹999/year plan.
Start this chapter free →Optics — FAQs
What are the key concepts in Class 11 Physics Optics?+
Light treated as rays: reflection at spherical mirrors with the mirror formula and sign convention, refraction and Snell's law, total internal reflection with its applications, refraction at a spherical surface leading to the lens maker's formula, lens power and combinations, the prism, and the microscope and telescope. Light treated as a wave: Huygens' principle and wavefronts, coherence and interference in Young's double-slit experiment with its fringe width, diffraction at a single slit and the width of the central maximum, how interference differs from diffraction, and polarisation with Malus's and Brewster's laws. Key ideas include Laws of reflection, Spherical mirrors, Sign convention, Mirror formula and magnification.
What does Class 11 Physics Chapter 303 (Optics) cover on XamBaaz?+
It has 40 NCERT-based MCQs on "Optics": 20 Easy and 20 Medium. Together they make 4 timed quizzes, and you never get the same set twice. Every question has an instant explanation. They help you prepare for CBSE & Maharashtra HSC Board exams, JEE Main, MHT-CET, JEE Advanced and NEET UG.
Are these "Optics" questions free to practise?+
Yes. Sign in with Google to practise "Optics" free. Full unlimited access is ₹999/year on a launch offer until 1 December 2026. No chapter is charged separately.
How should I revise "Optics" for the exam?+
Start with the Easy quiz to check your basics, then try Medium to practise applying them. There are 4 timed quizzes on this chapter, so you can come back for a fresh set instead of one you have seen. Read each explanation, retry the questions you miss, and track your accuracy until it stays high.
Are these "Optics" MCQs available with answers?+
Yes. 6 sample questions are shown here in full, each with the correct option and a step-by-step "Why" explanation. Sign in free with Google to start practising, with instant scoring.
Is there negative marking in the "Optics" quizzes?+
Yes. The timed quizzes use exam-style marking: +4 for a right answer, −1 for a wrong one and 0 for a skip, the same negative marking as JEE Main, JEE Advanced and NEET UG. MHT-CET and CBSE board papers have no negative marking. Our mocks for those are scored their way.
What are the important questions from Optics (Class 11 Physics)?+
The questions that matter most test Laws of reflection, Spherical mirrors, Sign convention, Mirror formula and magnification. This page shows 6 solved important MCQs with answers and explanations; all 40 questions on the chapter are available as timed quizzes once you sign in.
Is there an online quiz for Optics?+
Yes — Class 11 Physics Optics has timed online quizzes at Easy and Medium levels, with instant scoring and a worked explanation on every question. The first quiz on the chapter is free.